Q. How do I cite a memorandum of understanding?
This will depend on which citation method you are using (APA, MLA, Chicago, etc). In general, you would treat an MOU as a "unpublished or informally published work", and the 'authors' would be the various organizations.
There are guides to different citation styles at: http://csulb.libguides.com/style
Author, A. B. & Author, C. D. (Year). Title. Retrieved from http://exampleurl.com/
Lastname, Firstname and Firstname Lastname. "Title." Month Day, Year, Title of container, http://exampleurl.com/
Lastname, Firstname and Firstname Lastname. "Title." Unpublished manuscript, Month Day, Year.