The official source for APA Style. The Publication Manual of the American Psychological Association, Seventh Edition is the style manual of choice for writers, researchers, editors, students, and educators in the social and behavioral sciences, natural sciences, nursing, communications, education, business, engineering, and other fields.

The MLA Handbook is published by the Modern Language Association and is the only official, authorized book on MLA style.

The Chicago Manual of Style has been prepared with an eye toward how we find, create, and cite information that readers are as likely to access from their pockets as from a bookshelf. It offers updated guidelines on electronic workflows and publication formats, tools for PDF annotation and citation management, web accessibility standards, and effective use of metadata, abstracts, and keywords.