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Source Types

This guide shows students the definitions of the types of print and online materials they will find using the library's search Summon. This guide will also help students understand what their professors are requiring of them.

Understanding Source Types

As a student, you'll find many types of sources using the library's databases. Sometimes, professors will ask you to find specific sources, and sometimes, it's hard to tell what a source is because it's not labeled. Use this guide to help you determine if a source is the right one to use for your research project.

  Defining Primary, Secondary, and Tertiary Sources

  • Documents that provide information to help you gain a contemporary understanding of a non-contemporary subject.
    • Examples include anything originating at an historical point in time, such as diaries, newspaper reports, historical interviews, photographs, etc.
  • Also, when considered "original research," these are documents where researchers are studying a topic in a brand-new and unique way, with supporting data that those researchers gathered themselves.
  • You must interpret the information yourself because the author(s) will not provide an interpretation for you (Note: for this reason, some primary sources can be difficult to understand)
  • Example assignment where you may be asked to use primary sources:
    •  Write an essay that requires you to express your understanding of what the New York City survivors of the September 11th terrorist attacks saw that day.
  • Documents that provide background information about, or a synopsis of, a subject.
    • Examples include anything published after the fact (when discussing historical people, places, or topics), or scholarly materials talking about original research or primary sources, such as journal articles, books, magazine reports, etc..
  • The authors of these documents help you understand a specialized topic by providing their own analysis or interpretation (Note: for this reason, be aware of possible source bias)
  • Example assignment where you may be asked to use secondary sources:
    •  Write an essay that requires you to report on what political science scholars believe were the leading causes and events behind the September 11th terrorist attacks.
  • These documents provide a summary or overview of a topic. These sources are not usually credited to a particular author because they include items such as:
    • Encyclopedias, textbooks, dictionaries, and databases.
  • The publishers and editors of these documents often compile information from both primary and secondary sources.
  • These source types require less interpretive skills, since their main purpose is to index, abstract, organize, gather, and/or digest other sources.
  • Example assignment where you may be asked to use tertiary sources:
    •  Write a discussion post defining post-traumatic-stress-disorder (PTSD), including causes, treatments, and effects. .

Side-by-Side Comparisons of 3 Common Source Types 

Primary, Secondary, and Tertiary Source Types
Discipline Primary Source Examples Secondary Source Examples Tertiary Source Examples
Art and Architecture Painting by Manet Article critiquing art piece ArtStor database
Chemistry / Life Sciences Einstein’s Diary Monograph on Einstein’s life Dictionary on Theory of Relativity
Engineering / Physical Sciences Patent NTIS database User’s Manual
Humanities Letters by Dr. Martin Luther King, Jr. Web site on King’s writings Encylopedia on Civil Rights Movement
Social Sciences Notes taken by clinical psychologist Magazine article about the psychological condition Textbook on clinical psychology; DSM
Performing Arts Movie Filmed in 1942 Biography of the director Guide to the movie

 Additional Considerations to Make When Using These Source Types

  • Most researchers will benefit from using a combination of primary, secondary and tertiary sources
  • Some materials share features of BOTH primary and secondary sources
    • Example: The Norton Critical Edition of Moby-Dick by Herman Melville contains an original novel (primary sources) and scholarly essays about that novel (secondary sources)
  • Some materials could be considered primary OR secondary, depending upon the research focus
    • Example: The article “After 9/11: Goal Disruption, Emotional Support, and Psychological Health in a Lower Exposure Sample,” by MacGeorge et al., a scholarly research study published in 2007
      • This would be a secondary source for a history paper on the significance of 9/11)
      • This would be a primary source for a medical paper on post-traumatic stress reactions to acts of terrorism


Source Attribution