There is no universally accepted format for formatting and documenting citations in academic writing. Different disciplines, and even different journals within a discipline, are each likely to have their own partly rational and partly idiosyncratic customs and rules. Indeed an important part of scholarly training is learning what the rules are in one's particular field, so one can display the right kind of learning and professionalization. Fortunately for students and writing guides, a few documentation styles are especially widely used. Nuts and Bolts presents here guides to four common documentation styles: MLA, which is widely used in the humanities; APA, widely used in the social sciences; Chicago, also common in those two areas （and the format for those who favor footnotes）; and CBE, widely used in the natural sciences. Together these four guides should help you navigate most of the documentation formats you'll face in the typical range of college courses.