Your professor may have asked you to use primary sources for a research paper.  This guide will help you become familiar with the three main types of sources.

Primary Sources

  • Original documents with no interpretation, evaluation, or analysis
  • Original documents created contemporaneously with the event under discussion
  • Reflects the individual viewpoint of a participant or observer.
  • Usually found in library or manuscript collections. Many have also been copied onto microfilm, published, reissued, translated, or, in some instances, published digitally on the web.
  • The research librarians can assist you in locating primary sources.

housesen.jpgExamples of primary sources:

  • Books, magazine and newspaper articles published at the time
  • Speeches, interviews, letters, memoirs, autobiographies
  • Public opinion polls
  • Artifacts of all kinds: physical objects, furniture, tools, clothing, etc.
  • Photographs, audio recordings, movies and videos


Secondary Sources


  • Sources that interpret, evaluate, or analyze a primary source
  • At least one step removed from the event.

Examples of secondary sources:

  • Articles in scholarly journals that interpret literary or art works, historical events or persons. See "Types of Periodicals."
  • Commentaries and annotations accompanying the primary sources in the same volume.  These are often referred to as critical editions.
  • Books summarizing, synthesizing, or retelling historical events
  • Biographies, critical works, commentaries

Tertiary Sources

  • Sources that compile, summarize, digest, or index secondary sources

psychinfo.jpgExamples of tertiary sources:

  • Print or online indexing and abstracting resources, such as: Sociological Abstracts, MLA Bibliography, PsychInfo, Expanded Academic Index
  • Reference works, such as encyclopedias, dictionaries, atlases, handbooks, chronologies
  • Book-length bibliographies