The University of Michigan Library has a fabulous research guide on this topic. It is the clearest explanation of the main ideas and tools used in this complex endeavor. The guide mentions some subscription databases that we have. Those are listed and linked below. The links in the Michigan guide will not work for us here at SCU. One tool mentioned there, SCOPUS, we do not have a subscription for. However, you can get some information as part of a preview of Sources.