How do you cite:
Notes from class?
A recording you made of a visiting speaker?
An interview you had with someone?
Notes you wrote in another paper or publication?
A sound recording?
All of these things seem difficult to cite because they are not "standard" types of resources. While your style guide might have a structure on some of these, it might not. If there is no guidance on how to cite it you have a couple options:
1. Ask your professor.
2. Get creative (but not too creative)
Let's talk about option 2 for a second. What is a citation? A citation is a label that allows a reader to quickly identify and locate an information source. Things that go into a citation are things that would help the reader in this quest.
This generally includes something like: Creator of source, source name, source format, location of creation/publishing/etc., date created.
So for example, an interview I had with someone might look like:
Ross, Interview with Tarzan, The West Coast of Africa, 12 June 2011.
Check to see if there is an official way to cite your source first. If you have to get creative (a last resort thing) double check with your professor to make sure the citation you made works.