Chicago Manual of Style

the Essential Guide for Writers, Editors and Publishers

From Booklist:

From the 1906 first edition's limited focus as "a compilation of typographical rules" for books, it has evolved to provide guidance to authors and editors working in other forms and media such as journals, newsletters, Web sites, and even, with the fifteenth edition, American Sign Language. The editors now "assume throughout that most writers and editors, whether preparing print or nonprint works, use computer software." That assumption is most visible in the chapter dealing with presentation in type of mathematical expressions and formulas. Software has collapsed the division of labor between author and typesetter, giving the author the power to fulfill both roles simultaneously. Mathematicians have faced that special challenge; all scholars have been vexed by uncertainty about citing electronic resources.