I have provided a number of links to the various citation conventions for each discipline. Always confirm with your professor which citation style is preferred for work presented in his or her class.
The Online Writing Lab at Purdue has provided an extensive guide to Chicago formatting and style, which includes citation style and offers many examples.
AP Stylebook Online is a searchable, customizable resource for writers and editors. It’s updated throughout the year and valuable online-only resources, including Ask the Editor and Topical Guides, expand on the print book’s guidance. It’s mobile optimized so you can use it on your desktop, laptop, smartphone or tablet.
Provides recommendations on editorial style and publishing practices for the digital age. Now offering the full contents of the 16th and 15th editions, it is the must-have reference for everyone who works with words.