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Primary, Secondary, and Tertiary Sources: Overview


In this guide, users will learn what distinguishes each source type and locate primary source material from print, electronic, web-based, governmental, and archival material.  This Research Guide includes a "How To" tab, designed to instruct users on what search terms and descriptors to use when searching, as well as print and electronic guides which show how, where, and what to search.

Please note: The examples of available print, electronic, and web-based primary sources are just a sampling and by no means exhaustive.  We encourage you to visit the "How To" page for instructions on how to blend search terms relative to your research topic with subject headings that will assist you in locating primary sources. 

Primary Sources

"Primary sources are original materials. They are from the time period involved and have been filtered through interpretation or evaluation. Primary sources are original materials on which other research is based. They are usually the first formal appearance of results in physical, print, or electronic format. They present oringinal thinking, report discovery, or share new information."

Examples Include:

  • Art work - e.g. painting, sculptures, poems, musical scores, etc.
  • Artifacts - e.g. periodic clothing, coins, fossils, furniture, etc.
  • Audio recordings
  • Court records
  • Diaries
  • Eyewitness accounts
  • Internet communications - e.g. emails
  • Interviews
  • Legal documents - e.g. birth/death certificates, marriage licenses, etc.
  • Letters
  • Newspaper articles from period
  • Patents
  • Photographs
  • Speeches

Here are some questions that may help you evaluate primary sources:

  • What was the situation that prompted the writer to compose the document?
  • What was the writer's source of information?
  • What other primary sources might expand, clarify or contradict this document

Secondary Sources

"Secondary sources are less easily defined that primary sources. Generally, they are accounts written after the fact with the benefit of hindsight. They are interpretations and evaluations of primary sources. Secondary sources are not evidence but are commentary on and discussion of evidence."
Examples include:
  • Biographies
  • Commentaries
  • Histories
  • Literary Criticism
  • Magazine articles
  • Peer-reviewed journal articles
  • Reviews - e.g. book, performance

Here are some questions that may help you evaluate secondary sources:

  • What is the writer's expertise in this field?
  • What motivated the writer to compose this document?
  • How is this person evaluated by others who are known to be experts in this field?
  • What is the argument this writer is making about the topic?
  • What contradictions do other sources offer?
  • How credible are they?
  • How is this book/article evaluated by others in the field?
  • Is the information current? 

Tertiary Sources

"Tertiary sources consist of information which is a distillation and collection of primary and secondary sources."
Examples include:
  • Almanacs
  • Bibliographies
  • Dictionaries
  • Encyclopedias

Please Note: What sources are considered Secondary and Tertiary may depend on your own institution and more specifically, your discipline.