Whether you are using an article, book, website or visual material, a citation will require you to gather the following basic information:
The type of resource you are using (book, article, website, etc.) will dictate how this information should be presented (punctuation, etc.). A style guide will help direct your construction of citations.
Style guide is available here http://owl.english.purdue.edu/owl/resource/747/01/
BibMe A free online bibliographic management system. You can create a free account and store citations for all of your resources in there.