So far, we've talked a lot about scholarly information and popular information. Some information does not fit neatly into one category or the other. This page discusses some other types of information you may encounter or may be asked to use in a class.
Figure out what kind of "thing" you have (book, article, photograph, personal letter, government report, etc), and use the Citation Styles Guide to find an example.
Primary sources are documents or artifacts closest to the source--the "raw materials of history."
Examples include:
In the sciences, primary source can refer to an original research article.
The US government (as well as many governments around the world and international governing bodies, such as the United Nations) produces a vast amount of information. Some examples of government information include: legislation, case law, research and policy papers, census data, consumer publications, and much, much more.
Unless it is classified, most government information is freely available on the web. You can find much of it through the GovInfo portal.
GPO's official system for Federal information from all three branches of the U.S. Government. Provides free online access to official Federal Government publications.
"Grey literature" refers to stuff that is rigorous and well-researched, but doesn't neatly fit into the major categories of peer-reviewed articles and scholarly books.
Examples of grey literature:
Whether or not grey literature will be useful and appropriate depends on your information need and where the information is coming from.
