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Research Guides


Source Types

In the sciences, a primary source describes original research, while a secondary source analyzes or comments on a primary source or sources.  For example, a research article is primary literature because it describes an original experiment and its results, while a review article is secondary literature because it collates multiple research articles to describe the current state of the field. A tertiary source is an index or consolidation of primary and secondary sources.

Examples of primary sources: 

  • Research articles
  • Theses and dissertations
  • Conference proceedings
  • Reports
  • Patents 
  • Unrefined data sets 

Examples of secondary sources:

  • Review articles
  • Data compilations
  • Most books

Examples of tertiary sources:

  • Encyclopedias
  • Dictionaries
  • Field and identification guides

Academic Databases

Below are indexing article databases used for locating scholarly, peer-reviewed primary source (original research) articles. Be aware that secondary source articles, such as review articles, are also indexed in these databases and you'll need to evaluate each article for its relevance to your work.

Look for the 'Get this item' button to locate the article in the library's collections or request a copy of the article through Resource Sharing if we don't own it.

Books @ The Library

Because Environmental Analysis is a multidisciplinary topic, print items may be shelved in any location of The Claremont Colleges Library but are searchable via Library SearchIf you don't see a specific journal, ebook or print book or even article that you need you can request it by clicking on GET THIS ITEM


Books are are important in the sciences because they take a broader view of a topic that does a research article or a review article. When you are new to a topic or beginning a big research project (like a senior thesis or a literature review), starting with books is a better strategy than diving straight into research articles. 


In academic libraries in the United States, books are grouped by subject and the call numbers correspond to those subjects in a system called the Library of Congress Classification System. For more about how to find a book in our library, see our Finding a Book FAQ.

eBooks & References Resources

Consumer Information

Drug Product Information Databases

Evidence-Based Medicine Databases

Newspapers & News Resources

Film and Video Resources