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Education

Citation Examples

Grady, J. S., Her, M., Moreno, G., Perez, C., & Yelinek, J. (2019). Emotions in storybooks: A comparison of storybooks that represent ethnic and racial groups in the United States. Psychology of Popular Media Culture8(3), 207–217. https://doi.org/10.1037/ppm0000185

Jerrentrup, A., Mueller, T., Glowalla, U., Herder, M., Henrichs, N., Neubauer, A., & Schaefer, J. R. (2018). Teaching medicine with the help of “Dr. House”. PLoS ONE13(3), Article e0193972. https://doi.org/10.1371/journal.pone.019397

Parenthetical citations: (Grady et al., 2019; Jerrentrup et al., 2018)

Narrative citations: Grady et al. (2019) and Jerrentrup et al. (2018)

  • If a journal article has a DOI, include the DOI in the reference.
  • If the journal article does not have a DOI and is from an academic research database, end the reference after the page range (for an explanation of why, see the database information page). The reference in this case is the same as for a print journal article.
  • Do not include database information in the reference unless the journal article comes from a database that publishes original, proprietary content, such as UpToDate (see an example on the database information page).
  • If the journal article does not have a DOI but does have a URL that will resolve for readers (e.g., it is from an online journal that is not part of a database), include the URL of the article at the end of the reference.
  • If the journal article has an article number instead of a page range, include the article number instead of the page range (as shown in the Jerrentrup et al. example).

Rabinowitz, F. E. (2019). Deepening group psychotherapy with men: Stories and insights for the journey. American Psychological Association. https://doi.org/10.1037/0000132-000

Sapolsky, R. M. (2017). Behave: The biology of humans at our best and worst. Penguin Books.

Parenthetical citations: (Rabinowitz, 2019; Sapolsky, 2017)

Narrative citations: Rabinowitz (2019) and Sapolsky (2017)

  • If the book includes a DOI, include the DOI in the reference after the publisher name.
  • Do not include the publisher location.
  • If the book does not have a DOI and comes from an academic research database, end the book reference after the publisher name. Do not include database information in the reference. The reference in this case is the same as for a print book.

Schaefer, N. K., & Shapiro, B. (2019, September 6). New middle chapter in the story of human evolution. Science365(6457), 981–982. https://doi.org/10.1126/science.aay3550

Schulman, M. (2019, September 9). Superfans: A love story. The New Yorkerhttps://www.newyorker.com/magazine/2019/09/16/superfans-a-love-story

Parenthetical citations: (Schaefer & Shapiro, 2019; Schulman, 2019)

Narrative citations: Schaefer and Shapiro (2019) and Schulman (2019)

  • If a magazine article has a DOI, include the DOI in the reference.
  • If the magazine article does not have a DOI and is from an academic research database, end the reference after the page range. Do not include database information in the reference. The reference in this case is the same as for a print magazine article.
  • If the magazine article does not have a DOI but does have a URL that will resolve for readers (e.g., it is from an online magazine that is not part of a database), include the URL of the article at the end of the reference.
  • If the magazine article does not have volume, issue, and/or page numbers (e.g., because it is from an online magazine), omit the missing elements from the reference (as in the Schulman example).
 
Carey, B. (2019, March 22). Can we get better at forgetting? The New York Times https://www.nytimes.com/2019/03/22/health/memory-forgetting-psychology.html

Parenthetical citation: (Carey, 2019)

Narrative citation: Carey (2019)

  • If the newspaper article is from an academic research database, end the reference after the page range. Do not include database information in the reference. The reference in this case is the same as for a print newspaper article.
  • If the newspaper article has a URL that will resolve for readers (e.g., it is from an online newspaper), include the URL of the article at the end of the reference.
  • If the newspaper article does not have volume, issue, and/or page numbers (e.g., because it is from an online newspaper), omit the missing elements from the reference, as shown in the example.
  • If the article is from a news website (e.g., CNN, HuffPost)—one that does not have an associated daily or weekly newspaper—use the format for a webpage on a website instead.

Aron, L., Botella, M., & Lubart, T. (2019). Culinary arts: Talent and their development. In R. F. Subotnik, P. Olszewski-Kubilius, & F. 
C. Worrell (Eds.), The psychology of high performance: Developing human potential into domain-specific talent (pp. 345–359). American Psychological Association. https://doi.org/10.1037/0000120-016

Parenthetical citation: (Aron et al., 2019)

Narrative citation: Aron et al. (2019)

  • If the edited book chapter includes a DOI, include the chapter DOI in the reference after the publisher name.
  • Do not include the publisher location.
  • If the edited book chapter does not have a DOI and comes from an academic research database, end the edited book chapter reference after the publisher name. Do not include database information in the reference. The reference in this case is the same as for a print edited book chapter.
  • Do not create references for chapters of authored books. Instead, write a reference for the whole book and cite the chapter in the text if desired (e.g., Kumar, 2017, Chapter 2).
Merriam-Webster. (n.d.). Culture. In Merriam-Webster.com dictionary. Retrieved September 9, 2019, from https://www.merriam-webster.com/dictionary/culture

Parenthetical citation: (Merriam-Webster, n.d.)

Narrative citation: Merriam-Webster (n.d.)

  • Because entries in Merriam-Webster’s Dictionary are updated over time and are not archived, include a retrieval date in the reference.
  • Merriam-Webster is both the author and the publisher, so the name appears in the author element only to avoid repetition.
  • To quote a dictionary definition, view the pages on quotations and how to quote works without page numbers for guidance. Additionally, here is an example: Culture refers to the “customary beliefs, social forms, and material traits of a racial, religious, or social group” (Merriam-Webster, n.d., Definition 1a).
National Cancer Institute. (2019). Taking time: Support for people with cancer (NIH Publication No. 18-2059). U.S. Department of Health and Human Services, National Institutes of Health. https://www.cancer.gov/publications/patient-education/takingtime.pd

Parenthetical citation: (National Cancer Institute, 2019)

Narrative citation: National Cancer Institute (2019)

The specific agency responsible for the report appears as the author. The names of parent agencies not present in the group author name appear in the source element as the publisher. This creates concise in-text citations and complete reference list entries.

Harvard University. (2019, August 28). Soft robotic gripper for jellyfish [Video]. YouTube. https://www.youtube.com/watch?v=guRoWTYfxMs

Parenthetical citation: (Harvard University, 2019)

Narrative citation: Harvard University (2019)

  • Use the name of the account that uploaded the video as the author.
  • If the account did not actually create the work, explain this in the text if it is important for readers to know. However, if that would mean citing a source that appears unauthoritative, you might also look for the author’s YouTube channel, official website, or other social media to see whether the same video is available elsewhere.

APA Databases [@APA_Databases]. (2019, September 5). Help students avoid plagiarism and researchers navigate the publication process. More details available in the 7th edition @APA_Style table [Tweet]. Twitter. https://twitter.com/APA_Databases/status/1169644365452578823

Gates, B. [@BillGates]. (2019, September 7). Today, it’s difficult for researchers to diagnose #Alzheimers patients early enough to intervene. A reliable, easy and accurate diagnostic would [Thumbnail with link attached] [Tweet]. Twitter. https://twitter.com/BillGates/status/1170305718425137152

Parenthetical citations: (APA Databases, 2019; Gates, 2019)

Narrative citations: APA Databases (2019) and Gates (2019)

  • Present the name of the individual or group author the same as you would for any other reference. Then provide the Twitter handle (beginning with the @ sign) in square brackets, followed by a period.
  • Provide the first 20 words of the tweet as the title. Count a URL, a hashtag, or an emoji as one word each, and include them in the reference if they fall within the first 20 words.
  • If the tweet includes an image, a video, a poll, or a thumbnail image with a link, indicate that in brackets after the title: [Image attached], [Video attached], [Thumbnail with link attached].
  • The same format used for Twitter is also used for Instagram.  
News From Science. (2019, June 21). Are you a fan of astronomy? Enjoy reading about what scientists have discovered in our solar system—and beyond? This [Image attached] [Status update]. Facebook. https://www.facebook.com/ScienceNOW/photos/a.117532185107/10156268057260108/?type=3&theater

Parenthetical citation: (News From Science, 2019)

Narrative citation: News From Science (2019)

  • Provide the first 20 words of the Facebook post as the title. Count a URL or other link, a hashtag, or an emoji as one word each, and include them in the reference if they fall within the first 20 words. 
  • If a status update includes images, videos, thumbnail links to outside sources, or content from another Facebook post (such as when sharing a link), indicate that in square brackets.

Fagan, J. (2019, March 25). Nursing clinical brain. OER Commons. Retrieved September 17, 2019, from https://www.oercommons.org/authoring/53029-nursing-clinical-brain/view

National Institute of Mental Health. (2018, July). Anxiety disorders. U.S. Department of Health and Human Services, National Institutes of Health. https://www.nimh.nih.gov/health/topics/anxiety-disorders/index.shtml

Woodyatt, A. (2019, September 10). Daytime naps once or twice a week may be linked to a healthy heart, researchers say. CNN. https://www.cnn.com/2019/09/10/health/nap-heart-health-wellness-intl-scli/index.html

World Health Organization. (2018, May 24). The top 10 causes of deathhttps://www.who.int/news-room/fact-sheets/detail/the-top-10-causes-of-death

Parenthetical citations: (Fagan, 2019; National Institute of Mental Health, 2018; Woodyatt, 2019; World Health Organization, 2018)

Narrative citations: Fagan (2019), National Institute of Mental Health (2018), Woodyatt (2019), and World Health Organization (2018)

  • Provide as specific a date as is available on the webpage. This might be a year only; a year and month; or a year, month, and day.
  • Italicize the title of a webpage.
  • When the author of the webpage and the publisher of the website are the same, omit the publisher name to avoid repetition (as in the World Health Organization example).
  • When contents of a page are meant to be updated over time but are not archived, include a retrieval date in the reference (as in the Fagan example).
  • Use the webpage on a website format for articles from news websites such as CNN and HuffPost (these sites do not have associated daily or weekly newspapers). Use the newspaper article category for articles from newspaper websites such as The New York Times or The Washington Post.
  • Create a reference to an open educational resources (OER) page only when the materials are available for download directly (i.e., the materials are on the page and/or can be downloaded as PDFs or other files). If you are directed to another website, create a reference to the specific webpage on that website where the materials can be retrieved. Use this format for material in any OER repository, such as OER Commons, OASIS, or MERLOT.
  • Do not create a reference or in-text citation for a whole website. To mention a website in general, and not any particular information on that site, provide the name of the website in the text and include the URL in parentheses. For example, you might mention that you used a website to create a survey.

Archival document and collections are not presented in the APA Publication Manual, Seventh Edition. This content is available only on the APA Style websiteThis guidance has been expanded from the 6th edition.

Archival sources include letters, unpublished manuscripts, limited-circulation brochures and pamphlets, in-house institutional and corporate documents, clippings, and other documents, as well as such nontextual materials as photographs and apparatus, that are in the personal possession of an author, form part of an institutional collection, or are stored in an archive such as the Archives of the History of American Psychology at the University of Akron or the APA Archives. For any documents like these that are available on the open web or via a database (subscription or nonsubscription), follow the reference templates shown in Chapter 10 of the Publication Manual.

The general format for the reference for an archival work includes the author, date, title, and source. The reference examples shown on this page may be modified for collections requiring more or less specific information to locate materials, for different types of collections, or for additional descriptive information (e.g., a translation of a letter). Authors may choose to list correspondence from their own personal collections, but correspondence from other private collections should be listed only with the permission of the collector.

Keep in mind the following principles when creating references to archival documents and collections:

  • As with any reference, the purpose is to direct readers to the source, despite the fact that only a single copy of the document may be available and readers may have some difficulty actually seeing a copy.
  • Include as much information as is needed to help locate the item with reasonable ease within the repository. For items from collections with detailed finding aids, the name of the collection may be sufficient; for items from collections without finding aids, more information (e.g., call number, box number, file name or number) may be necessary to help locate the item.
  • If several letters are cited from the same collection, list the collection as a reference and provide specific identifying information (author, recipient, and date) for each letter in the in-text citations (see Example 3).
  • Use square brackets to indicate information that does not appear on the document.
  • Use “ca.” (circa) to indicate an estimated date (see Example 5).
  • Use italics for titles of archival documents and collections; if the work does not have a title, provide a description in square brackets without italics.
  • Separate elements of the source (e.g., the name of a repository, library, university or archive, and the location of the university or archive) with commas. End the source with a period.
  • If a publication of limited circulation is available in libraries, the reference may be formatted as usual for published material, without the archival source.
  • Note that private letters (vs. those in an archive or repository) are considered personal communications and cited in the text only.
 
1. Letter from a repository

Frank, L. K. (1935, February 4). [Letter to Robert M. Ogden]. Rockefeller Archive Center (GEB Series 1.3, Box 371, Folder 3877), Tarrytown, NY, United States.

  • Parenthetical citation: (Frank, 1935)
  • Narrative citation: Frank (1935)
  • Because the letter does not have a title, provide a description in square brackets.
2. Letter from a private collection

Zacharius, G. P. (1953, August 15). [Letter to William Rickel (W. Rickel, Trans.)]. Copy in possession of Hendrika Vande Kemp.

  • Parenthetical citation: (Zacharius, 1953)
  • Narrative citation: Zacharius (1953)
  • In this example, Hendrika Vande Kemp is either the author of the paper or the author of the paper has received permission from Hendrika Vande Kemp to cite a letter in Vande Kemp’s private collection in this way. Otherwise, cite a private letter as a personal communication.
3. Collection of letters from an archive

Allport, G. W. (1930–1967). Correspondence. Gordon W. Allport Papers (HUG 4118.10), Harvard University Archives, Cambridge, MA, United States.

  • Parenthetical citation: (Allport, 1930–1967)
  • Narrative citation: Allport (1930–1967)

To cite specific letters in the text, provide the author and range of years as shown in the reference list entry, plus details about who wrote the specific letter to whom and when the specific letter was written.

  • Parenthetical citation: (Allport, 1930–1967, G. Boring to Allport, December 26, 1937)
  • Narrative citation: Allport (1930–1967, Allport to G. Boring, March 1, 1939)
  • Use the parenthetical citation format to cite a letter that E. G. Boring wrote to Allport because Allport is the author in the reference. Use either the parenthetical or narrative citation format to cite letters that Allport wrote.
4. Unpublished papers, lectures from an archive or personal collection

Berliner, A. (1959). Notes for a lecture on reminiscences of Wundt and Leipzig. Anna Berliner Memoirs (Box M50), Archives of the History of American Psychology, University of Akron, Akron, OH, United States.

  • Parenthetical citation: (Berliner, 1959)
  • Narrative citation: Berliner (1959)
5. Archival/historical source for which the author and/or date is known or is reasonably certain but not stated on the document

Allport, A. (presumed). (ca. 1937). Marion Taylor today—by the biographer [Unpublished manuscript]. Marion Taylor Papers, Schlesinger Library, Radcliffe College, Cambridge, MA, United States.

  • Parenthetical citation: (Allport, ca. 1937)
  • Narrative citation: Allport (ca. 1937)
  • Because the author is reasonably certain but not stated on the document, place the word “presumed” in parentheses after the name, followed by a period.
  • Because the date is reasonably certain but not stated on the document, the abbreviation “ca.” (which stands for “circa”) appears before the year in parentheses.
6. Archival source with group author

Subcommittee on Mental Hygiene Personnel in School Programs. (1949, November 5–6). Meeting of Subcommittee on Mental Hygiene Personnel in School Programs. David Shakow Papers (M1360), Archives of the History of American Psychology, University of Akron, Akron, OH, United States.

  • Parenthetical citation: (Subcommittee on Mental Hygiene Personnel in School Programs, 1949)
  • Narrative citation: Subcommittee on Mental Hygiene Personnel in School Programs (1949)
7. Interview recorded and available in an archive

Smith, M. B. (1989, August 12). Interview by C. A. Kiesler [Tape recording]. President’s Oral History Project, American Psychological Association, APA Archives, Washington, DC, United States.

  • Parenthetical citation: (Smith, 1989)
  • Narrative citation: Smith (1989)
  • For interviews and oral histories recorded in an archive, list the interviewee as the author. Include the interviewer’s name in the description.
8. Transcription of a recorded interview, no recording available

Sparkman, C. F. (1973). An oral history with Dr. Colley F. Sparkman/Interviewer: Orley B. Caudill. Mississippi Oral History Program (Vol. 289), University of Southern Mississippi, Hattiesburg, MS, United States.

  • Parenthetical citation: (Sparkman, 1973)
  • Narrative citation: Sparkman (1973)
  • For interviews and oral histories recorded in an archive, list the interviewee as the author. Include the interviewer’s name in the description.
9. Newspaper article clipping, historical, in personal collection

Psychoanalysis institute to open. (1948, September 18). [Clipping from an unidentified Dayton, OH, United States, newspaper]. Copy in possession of author.

  • Parenthetical citation: (“Psychoanalysis Institute to Open,” 1948)
  • Narrative citation: “Psychoanalysis Institute to Open” (1948)
  • Use this format only if you are the person who is in possession of the newspaper clipping.
10. Historical publication of limited circulation

Sci-Art Publishers. (1935). Sci-Art publications [Brochure]. Roback Papers (HUGFP 104.50, Box 2, Folder “Miscellaneous Psychological Materials”), Harvard University Archives, Cambridge, MA, United States.

  • Parenthetical citation: (Sci-Art Publishers, 1935)
  • Narrative citation: Sci-Art Publishers (1935)
11. Archived photographs, no author and no title

[Photographs of Robert M. Yerkes]. (ca. 1917–1954). Robert Mearns Yerkes Papers (Box 137, Folder 2292), Manuscripts and Archives, Yale University Library, New Haven, CT, United States.

  • Parenthetical citation: ([Photographs of Robert M. Yerkes], ca. 1917–1954)
  • Narrative citation: [Photographs of Robert M. Yerkes] (ca. 1917–1954)
  • Because the archived photographs do not have a title, provide a bracketed description instead.
  • Because the archived photographs do not have an author, move the bracketed description to the author position of the reference.
12. Microfilm

U.S. Census Bureau. (1880). 1880 U.S. census: Defective, dependent, and delinquent classes schedule: Virginia [Microfilm]. NARA Microfilm Publication T1132 (Rolls 33–34), National Archives and Records Administration, Washington, DC, United States.

  • Parenthetical citation: (U.S. Census Bureau, 1880)
  • Narrative citation: U.S. Census Bureau (1880)

Read the full APA guidelines on citing ChatGPT 

 

OpenAI. (2023). ChatGPT (Mar 14 version) [Large language model]. https://chat.openai.com/chat

  • Parenthetical citation: (OpenAI, 2023)
  • Narrative citation: OpenAI (2023)

 

Author: The author of the model is OpenAI.

Date: The date is the year of the version you used. Following the template in Section 10.10, you need to include only the year, not the exact date. The version number provides the specific date information a reader might need.

Title: The name of the model is “ChatGPT,” so that serves as the title and is italicized in your reference, as shown in the template. Although OpenAI labels unique iterations (i.e., ChatGPT-3, ChatGPT-4), they are using “ChatGPT” as the general name of the model, with updates identified with version numbers.

The version number is included after the title in parentheses. The format for the version number in ChatGPT references includes the date because that is how OpenAI is labeling the versions. Different large language models or software might use different version numbering; use the version number in the format the author or publisher provides, which may be a numbering system (e.g., Version 2.0) or other methods.

Bracketed text is used in references for additional descriptions when they are needed to help a reader understand what’s being cited. References for a number of common sources, such as journal articles and books, do not include bracketed descriptions, but things outside of the typical peer-reviewed system often do. In the case of a reference for ChatGPT, provide the descriptor “Large language model” in square brackets. OpenAI describes ChatGPT-4 as a “large multimodal model,” so that description may be provided instead if you are using ChatGPT-4. Later versions and software or models from other companies may need different descriptions, based on how the publishers describe the model. The goal of the bracketed text is to briefly describe the kind of model to your reader.

Source: When the publisher name and the author name are the same, do not repeat the publisher name in the source element of the reference, and move directly to the URL. This is the case for ChatGPT. The URL for ChatGPT is https://chat.openai.com/chat. For other models or products for which you may create a reference, use the URL that links as directly as possible to the source (i.e., the page where you can access the model, not the publisher’s homepage).

What to include and what to exclude

Works Included in a Reference List

The reference list provides a reliable way for readers to identify and locate the works cited in a paper. APA Style papers generally include reference lists, not bibliographies.

In general, each work cited in the text must appear in the reference list, and each work in the reference list must be cited in the text. Check your work carefully before submitting your manuscript or course assignment to ensure no works cited in the text are missing from the reference list and vice versa, with only the following exceptions.

Works Excluded From a Reference List

There are a few kinds of works that are not included in a reference list. Usually a work is not included because readers cannot recover it or because the mention is so broad that readers do not need a reference list entry to understand the use.

Information on works included in a reference list is covered in Sections 2.12 and 8.4 of the APA Publication Manual, Seventh Edition

*This guidance has been expanded from the 6th edition.*

  • Personal communications such as emails, phone calls, or text messages are cited in the text only, not in the reference list, because readers cannot retrieve personal communications.
  • General mentions of whole websites, whole periodicals, and common software and apps in the text do not require in-text citations or reference list entries because the use is broad and the source is familiar.
  • The source of an epigraph does not usually appear in the reference list unless the work is a scholarly book or journal. For example, if you open the paper with an inspirational quotation by a famous person, the source of the quotation does not appear in the reference list because the quotation is meant to set the stage for the work, not substantiate a key point.   
  • Quotations from research participants in a study you conducted can be presented and discussed in the text but do not need citations or reference list entries. Citations and reference list entries are not necessary because the quotations are part of your original research. They could also compromise participants’ confidentiality, which is an ethical violation.
  • References included in a meta-analysis, which are marked with an asterisk in the reference list, may be cited in the text (or not) at the author’s discretion. This exception is relevant only to authors who are conducting a meta-analysis.

DOIs and URLs

The DOI or URL is the final component of a reference list entry. Because so much scholarship is available and/or retrieved online, most reference list entries end with either a DOI or a URL.

  • A DOI is a unique alphanumeric string that identifies content and provides a persistent link to its location on the internet. DOIs can be found in database records and the reference lists of published works.
  • A URL specifies the location of digital information on the internet and can be found in the address bar of your internet browser. URLs in references should link directly to the cited work when possible.

Follow these guidelines for including DOIs and URLs in references:

  • Include a DOI for all works that have a DOI, regardless of whether you used the online version or the print version.
  • If a print work does not have a DOI, do not include any DOI or URL in the reference.
  • If an online work has both a DOI and a URL, include only the DOI.
  • If an online work has a URL but no DOI, include the URL in the reference as follows:
    • For works without DOIs from websites (not including academic research databases), provide a URL in the reference (as long as the URL will work for readers).
    • For works without DOIs from most academic research databases, do not include a URL or database information in the reference because these works are widely available. The reference should be the same as the reference for a print version of the work.
    • For works from databases that publish original, proprietary material available only in that database (such as the UpToDate database) or for works of limited circulation in databases (such as monographs in the ERIC database), include the name of the database or archive and the URL of the work. If the URL requires a login or is session-specific (meaning it will not resolve for readers), provide the URL of the database or archive home page or login page instead of the URL for the work. See the page on including database information in references for more information. 
    • If the URL is no longer working or no longer provides readers access to the content you intend to cite, follow the guidance for works with no source.
  • Other alphanumeric identifiers such as the International Standard Book Number (ISBN) and the International Standard Serial Number (ISSN) are not included in APA Style references.

Follow these guidelines to format DOIs and URLs:

  • Present both DOIs and URLs as hyperlinks (i.e., beginning with “http:” or “https:”).
  • Because a hyperlink leads readers directly to the content, it is not necessary to include the words “Retrieved from” or “Accessed from” before a DOI or URL.
  • It is acceptable to use either the default display settings for hyperlinks in your word-processing program (e.g., usually blue font, underlined) or plain text that is not underlined.
  • Leave links live if the work is to be published or read online.
  • Follow the current recommendations of the International DOI Foundation to format DOIs in the reference list, which as of this publication is as follows:

https://doi.org/xxxxx

  • The string “https://doi.org/” is a way of presenting a DOI as a link, and “xxxxx” refers to the DOI number.
  • The preferred format of the DOI has changed over time. Although older works use previous formats (e.g., “http:/dx.doi.org/” or “doi:” or “DOI:” before the DOI number), in your reference list, standardize DOIs into the current preferred format for all entries. For example, use https://doi.org/10.1037/a0040251 in your reference even though that article, published in 2016, presented the number in an older format.
  • Copy and paste the DOI or URL from your web browser directly into your reference list to avoid transcription errors. Do not change the capitalization or punctuation of the DOI or URL. Do not add line breaks manually to the hyperlink; it is acceptable if your word-processing program automatically adds a break or moves the hyperlink to its own line.
  • Do not add a period after the DOI or URL because this may interfere with link functionality.

When a DOI or URL is long or complex, you may use shortDOIs or shortened URLs if desired.

  • Use the shortDOI service provided by the International DOI Foundation to create shortDOIs. A work can have only one DOI and only one shortDOI; the shortDOI service will either produce a new shortDOI for a work that has never had one or retrieve an existing shortDOI.
  • Some websites provide their own branded shortened URLs, and independent URL shortening services are available as well. Any shortened URL is acceptable in a reference as long as you check the link to ensure that it takes you to the correct location.