Look at the publication date of the book and the birth/death dates of the author. The date of the original publication may give you an indication that you have a primary source. If you have a reprinted book, look for the original publication date. If the birth/death dates of the author are such that he/she lived during the time of your event, you might have a primary source.
Look at the notes in the record. There might be notes in the record that describe the material and give clues as to whether or not it is a primary source. For instance, if there is a note indicating that the work is a facsimile or a reprint, then you might have a primary source.
To find diaries, letters, autobiographies, personal papers, etc., search a person’s name as an author (not as a subject, because that will find materials about them instead of items he/she wrote).
To see what actual manuscripts we have at Swem Library, do an advanced search in the online catalog:
Click on the Advanced Search button.
On the top half of the screen, type what you’re looking for (author, subject, etc.) In another search box type "manuscript".
The following words are clues that the material might contain primary-source material. These words usually appear in the title or as part of the subject heading:
You can also combine a primary-source format word with an event or person
Examples: letters and lincoln, diaries and civil war
The Special Collections Research Center (SCRC) has extensive holdings of manuscripts, university archives, and rare books. There are a variety of tools available to guide you in finding materials in the SCRC, including the SCRC Collections Database. You might find it helpful to begin your search at the SCRC's Search Tools page.
Don't forget that you also may contact the SCRC staff (spcoll@wm.edu or 757-221-3090) or come into the Special Collections Research Center in person and consult with the staff member on duty for guidance.