Chicago/Turabian Citation Style Guide (UWL History Department)
Turabian, Kate L. A Manual for Writers of Research Papers, Theses, and Dissertations, Seventh Edition: Chicago Style for Students and Researchers. Chicago: University of Chicago Press, 2007.
which is itself based on:
Chicago Manual of Style, 15th edition, 2003.
The most recent editions of Turabian (9th, 2018) and the Chicago Manual of Style (17th, 2017) are available at Murphy Library in the Ready Reference collection. The latest version of the Chicago Manual of Style is also available online.
Please check with your instructor before you choose a manual to consult.