Books related to ecology can be found in several sections of the library, primarily in the GEs and GFs.
In one of these library databases
In one of these collections
If you need a book or article that PSU does not have you can request the article through Interlibrary Loan.
This service is free to all PSU students, faculty, and staff.
http://library.plymouth.edu/noodletoolsNoodleTools can help you create, manage, and save citations in a variety of citation styles.
Below are links to the style manuals for some other common citation styles.
The Purdue OWL has great information on APA, MLA, and Chicago.