The University of Kansas Libraries

What types of sources are there?

The Big Three

Primary Sources:

Primary sources are original materials on which other research is based and present original thought, report on discoveries, or share new information.  They are usually the first formal appearance of results in the print or electronic literature (for example, the first publication of the results of scientific investigations is a primary source.) These sources present information in its original form, not interpreted, condensed or evaluated by others.  Primary resources are from the time period (something written close to when what it is recording happened is likely to be a primary source.)

• scientific journal articles reporting experimental research results
• proceedings of Meetings, Conferences and Symposia.
• technical reports
• sets of data, such as census statistics
• works of literature (such as poems and fiction)
• diaries, autobiographies,  letters and correspondence
• speeches, interviews, surveys and fieldwork
• newspaper articles (may also be secondary)
• government documents
• photographs and works of art
• Internet communications on email, listservs, and newsgroups

Secondary Sources:

Secondary sources are less easily defined than primary sources. A newspaper article is a primary source if it reports events, but a secondary source if it analyses and comments on those events. In science, secondary sources are those which simplify the process of finding and evaluating the primary literature. More generally, secondary sources:

• describe, interpret, analyze and evaluate the primary sources
• comment on and discuss the evidence provided by primary sources
• works which are one or more steps removed from the event or information they refer to, being written after the fact with the benefit of hindsight.

• journal articles, particularly in disciplines other than science (may also be primary)
• newspaper and popular magazine articles (may also be primary)
• dissertations or theses (more usually primary)
• monographs (other than fiction and autobiography)
• review articles and literature reviews
• bibliographies (may also be tertiary)
• dictionaries and encyclopedias (may also be tertiary)
• handbooks and data compilations (may also be tertiary)
• textbooks (may also be tertiary)

Tertiary Sources:

These are works which list primary and secondary resources in a specific subject area.  They often index, organize and compile citations to, and show you how to use, secondary (and sometimes primary) sources.  Many times, these are materials in which the information from secondary sources has been "digested" - reformatted and condensed, to put it into a convenient, easy-to-read form. Tertiary sources are often once removed in time from secondary sources.  Because the nature of this type of source is often broad, usually much of the finer details of the larger work are forgotten or left out, so it is a good idea to refer back to your primary and secondary sources for use in your work.

• almanacs and fact books
• bibliographies (may also be secondary)
• chronologies
• dictionaries and encyclopedias (may also be secondary)
• directories
• guidebooks, manuals etc
• textbooks (may also be secondary)