There are literally dozens of guides in print and on the Web. Each discipline has its own guide or guides and many publications have created their own style. Writers must adhere to the 'publisher' demands. There are several places to look for the correct information. This might be a good first place to look.
Many publications note their required style in a section usually called instructions to authors.
There are several web sites that discuss citation. Again, find the one or ones that will work for your need. A list of Web sites follows, then a bibliography of books that you might find useful. The Chicago Manual of Style , 14th ed. University of Chicago Press, 1994.