On Google Scholar
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Related guides
Selected databases
- Agricultural and Environmental Science Database This link opens in a new window
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Includes AGRICOLA, TOXLINE, ESPM (Environmental Sciences and Pollution Management) and 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, and more.
- Gale in Context: Environmental Studies This link opens in a new window Focuses on the physical, social, and economic aspects of environmental issues. Topic, organization, and country portals form research centers around issues covering energy systems, health care, agriculture, climate change, population, and economic development. (formerly GREENR database)
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Subject specific databases often cover that area's literature in more depth than a multidisciplinary database.
- Web of Science 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, and humanities, as published in journals, conference proceedings, symposia, seminars, colloquia, and workshops across the globe.
- Scopus This link opens in a new window
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A citation and abstracting database covering thousands of active titles, primarily peer-reviewed journals. Also includes eBooks, major reference works and graduate level textbooks. Emphasis on social sciences, arts and humanities, but also includes science, technology and 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.
Comprehensive database for chemical literature, indexing journal articles and patent records, and chemical substances and reactions. You can search by topic, author, and substances by name or CAS Registry Number, or use the editor to draw chemical structures, substructures, or reactions. - PubMed This link opens in a new window
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A free resource providing access to biomedical and life sciences literature. Contains millions of citations and 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. To access articles from UD subscribed titles you must be a UD student or staff member.
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 ...
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.