On Google Scholar
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Related guides
Selected databases
- Web of Science (WoS) This link opens in a new window
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A collection of databases that can be searched individually or in various combinations. WoS indexs the world’s leading scholarly literature in the sciences, social sciences, arts, & humanities, as published in journals, conference proceedings, symposia, seminars, colloquia, & workshops across the globe. - Scopus This link opens in a new window
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A citation & abstracting database covering thousands of active titles, primarily peer-reviewed journals. Also includes eBooks, major reference works & graduate level textbooks. Emphasis on social sciences, arts & humanities, but also includes science, technology & medicine. Includes thousands of Open Access journals, conference proceedings, trade publications, book series, and patents. (Coverage: Primarily 1970-present. Some pre-1970 records going back to 1788) - SciFinder-n This link opens in a new window
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To use SciFinder, you *must register* and provide your UD email. Registration details and additional information.
Comprehensive database for the chemical literature. Contains other scientific disciplines as well. - PubMed This link opens in a new window
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A free resource providing access to biomedical & life sciences literature. Contains millions of citations & abstracts, but does not include full-text articles. However, links to the full-text are often present from other sources, such UD subscribed titles, publisher websites, or PubMed Central.
These multidisciplinary databases cover a wide range of fields. Web of Science concentrates on the core journals in the fields, while Scopus covers a wider range of titles.. Scifinder is focused on the chemistry literature, and PubMed covers ...
- Agricultural & Environmental Science Database This link opens in a new window
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Includes AGRICOLA, TOXLINE, ESPM (Environmental Sciences & Pollution Management) & Environmental Impact Statements (EIS). Provides full-text titles from around the world. - GreenFILE This link opens in a new window
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Covers all aspects of human impact to the environment, including content on global warming, green building, pollution, sustainable agriculture, renewable energy, recycling, & more.
- Gale in Context: Environmental Studies This link opens in a new window
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Focuses on the study of sustainability & the environment. Topics include ecosystems, global warming, food safety, & introductions to environmental disasters.
Subject specific databases often cover that area's literature in more depth than a multidisciplinary database.
Primary literature and peer-reviewed journals
Primary sources represent original research from the discovery stage to official publications:
- R&D stage (lab notebooks)
- Informal sharing (communication between colleagues, departmental colloquia)
- preliminary communication (letters to the Editor, Letters Journals, Biosequence data)
- formalized documents (patents, conference proceedings, technical reports, dissertations & theses, journal articles)
Secondary sources organize, repackage and concentrate the published information from primary sources into:
- Indexes & Abstracts, Bibliographies, Databases (bibliographic, bioinformatics)
- Handbooks, Dictionaries, Directories, Yearbooks, Almanacs
- Encyclopedias, Treatises, Monographs or Books, Reviews
Secondary sources are where you go to find general overviews of research occurring in the field or interpretations of past research.
Is a review article considered a primary source?
No, because the authors are not reporting their own original research, but rather, they are discussing other authors' research in order to present a review of the subject area or topic.
How can I tell if a journal is peer-reviewed?
- In a database, look for a filter that will limit the results to peer-review journals: "Peer-Reviewed Journals", "Scholarly (Peer Reviewed) Journals", or "Scholarly Journal"
- Search for the title on the Library's E-Journals page, and look for the "Peer-Reviewed" designation.
- Go to the journal's home page for more information about the journal.
NOTE: Not all items published in a peer-reviewed journal are necessarily peer-reviewed, for example editorials or letters.