From the APA Style Blog. Copies of the APA style manual can be found in the library.
"The guidance on p. 179 of the Publication Manual about citing personal communications mentions “personal interviews” as one example. Let’s say you interview a professor about her lifetime of work in the field of industrial and organizational psychology. Because a reader would not be able to find your interview in print or online, no recoverable data are available. You’ll need to use the “personal communication” in-text citation style shown on p. 179."
When using information from another source you must give credit to the original author or you are plagiarizing. You give credit by citing the source. Make sure your citation contains everything you would need to backtrack and find the information again. It is best to pick one citation style and be consistent.