Primary Sources

A primary source is a document that contains firsthand information or original data on a topic.

If you are researching a certain time period, a primary source is one that was created during the time being studied.

Examples of primary sources include:

For more information: Guide on Primary, Secondary, and Tertiary Sources by the University of Maryland Libraries.

NU Search

Find primary sources in the library’s collections.

Enter your search using the following format: [topic keyword AND su:sources].

Primary sources in the library catalog generally have “sources” as a subject heading. [su:sources] searches for resources with “sources” as one of the subject headings.

Example searches:

Primary Sources in NU Reference

Browse and/or search primary sources in the library’s collection of online reference sources (Gale Virtual Reference Library). Includes U.S. History, Medicine, Crime, and Human Rights.

Google Books

If you are looking for primary sources on a historical topic, Google has digitized many out-of-copyright and public domain books from the world’s research library collections. Use Google’s Advanced Book Search and limit your search to Full view only to find books available in full text.


Guide to searching NU’s archives collections and other freely available digital archives.


Guide to searching NU’s newspaper collections.