OneSearch - If the Pfau Library has it, it will be in the CSUSB area of OneSearch. If not, use the all-CSU portion of OneSearch and request it using CSU+. For items not held by any of the CSU campuses, you will need to order it through interlibrary loan (ILL).
Melvyl - all UC Libraries
Below are listed the most productive databases for research in your field.