Systems for citing ancient texts vary from one author to another; most systems involve book and chapter number and/or line number (NOT page number). If in doubt, please consult your instructor. See also:
Generally, when citing ancient texts, you will use the following format:
[Author], [Title] [Book/Section. (Poem, if applicable).] [Line numbers cited.]
Homer, Iliad 18.141-143.
Plato, Symposium 215a3-218b7.
For help citing secondary sources, take a look at the library's citation guide. This guide gives examples for how to cite in various formats, as well as tips for distinguishing between source types.