Here is a list of databases that you can use to find scholarly articles on your subject.
Penn's subscription currently includes all the available collections:
Access to journals from JSTOR is restricted to current Penn faculty, staff and students.
Printing from the JSTOR database requires downloading a helper application called JPrint.
There are many different databases that you can use for your research, but before you get started, here are some videos to help you understand the basics of academic research.