“APA style” refers to the American Psychological Association’s formatting rules for citing sources and overall formatting of research papers. APA style is used by many disciplines including Psychology, Nursing, Communication Studies, and Business.
This guide is a general overview of how to cite common types of sources using APA style. For more complex APA style questions, please consult the official APA formatting rules found in The Publication Manual of the American Psychological Association, 6th ed.
Look here for answers to tricky questions like how to cite obscure source types and for explanations of APA rules. This is a good place to go if you have consulted the APA manual and still have questions.