When you use someone else's words or ideas in your papers, you should create In-text citations (within the paper) and References list citations (at the end of the paper). Each In-text citation should lead to a References list citation, and each References list citation should come from an In-text citation.
Use the Publication manual of the American Psychological Association (6th edition) to correctly cite your sources.
Use the Purdue OWL APA Guide (6th ed.) to put together your APA in-text and references list citations:
Use the APA Style website or take the Basics of APA Style tutorial for help with putting together your citations. Read through the short blog entry The Proper Use of Et Al in APA Style for explanations and examples of how to handle in-text and Reference List citations for various numbers of authors.