Chicago Style is the standard for many university press publishers and is used by many programs within the humanities. The style is flexible and is not tied to a discipline, although history is the discipline most closely associated with the notes and bibliography version of the style.
Both the American Anthropological Association and the American Political Science Association based their style guides on Chicago Style, but neither guide has been updated to reflect the latest edition of the Chicago Manual of Style. If you are required to use either of these, each is freely available in PDF format:
American Anthropological Association Style Guide (last revised 2009)
American Political Science Association Style Guide (last revised 2006)
1. The Chicago Manual of Style. 16th edition.
LOCATION: Cabell Reference Desk Z253 .U69 2010
The Chicago Manual of Style Online
Searchable and browsable. Includes both the 16th and the 15th editions.
2. A Manual for Writers of Term Papers, Theses, and Dissertations. 8th edition.
LOCATION: Cabell Reference LB2369 .T8 2013
(NOTE: This manual, commonly referred to as Turabian, consists of the elements of Chicago style most suitable for the individual writer, students in particular)