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Periodicals: Source Types

What are periodicals? How do I find periodicals? What kinds of periodicals are there? How do I cite periodical articles?

Primary Sources

Primary Source - Ford Pardon of NixonFor some research projects you may be required to use Primary Sources. A primary source provides direct or firsthand evidence about an event, object, person, or work of art.  Primary sources include:

  • original historical and legal documents;
  • eyewitness accounts;
  • results of experiments;
  • statistical data;
  • pieces of creative writing;
  • audio and video recordings;
  • speeches;
  • art objects;
  • relics or artifacts;
  • interviews;
  • surveys;
  • fieldwork;
  • Internet communications (email, blogs, listservs, etc.)

"In the natural and social sciences, primary sources are often empirical studies - research where an experiment was performed or a direct observation was made. The results of thse first-hand empirical studies are typically found in scholarly articles or papers delivered at conferences." (

Below is a list of some well-known primary source websites.  Be sure to check the [Websites] tabs on individual [Subject Guides] for other discipline-specific primary source websites.

Secondary Sources

Secondary Sources: Secondary Source Journal

  • describe;
  • discuss;
  • interpret;
  • comment upon;
  • analyze;
  • evaluate;
  • summarize;
  • process primary sources.

Periodicals often provide secondary source materials in articles in newspapers or popular magazines, or in book or movie reviews. 

If a scholarly periodical (journal) article mentions or critiques another scholar's original research, it is secondary source material.

Tertiary Sources

Tertiary sources consist of information which is a compilation or distillation of primary and secondary sources. Usually information is provided factually and does not critique or provide analysis. Tertiary sources may include:

  • almanacs;
  • bibliographies;
  • chronologies;
  • databases;
  • dictionaries;
  • directories;
  • encyclopedia;
  • Indexes & abstracts;
  • textbooks;
  • Wikipedia.

Tertiary Sources encyclopedia