A Manual for Writers of Research Papers, Theses, and Dissertations, known simply as "Turabian" is the authoritative student resource on "Chicago Style." The 9th edition of "Turabian" is a derivative of the Chicago Style Manual 17th ed. The two citations styles are almost identical. Turabian offers a guide to the two methods of Chicago Style sources citation: 1. Notes- Bibliography and 2. Author-date style. The recommendations in Turabian diverge in small ways from Chicago Style to better suit the requirements of academic writing rather than published works. Be sure to follow the guidelines provided by your professor.