Think about what kinds of primary sources might be related to your topic:
A primary source...was created at the time of the event...or by people who were observers of, or participants in, that event. ...
The medium of the primary source can be anything, including written texts, objects, buildings, films, paintings, cartoons, etc.
--Professor Elspeth H. Brown, Dept. of History, University of Toronto.
See: http://www.writing.utoronto.ca/advice/specific-types-of-writing/history
For another definition, see Yale University: http://primarysources.yale.edu
Cholera bulletin Gore (Ont.: District). Medical Board. Ephemera, 1832. Toronto Public Library.
You might find references to primary sources in the works cited or bibliography of a reference tool and/or a secondary source (journal article, book, or book chapter)