Dissertations offer a depth and richness of information found in few other places. You can find information about dissertations in subject-specific databases, as well as databases made just for dissertations.
If you find a dissertation citation and need the full-text, you can request a copy be purchased for you through Interlibrary Loan. There's no charge for requesting copies of dissertations, but remember that these tend to be quite long and in-depth.
Sometimes a dissertation gets published as a full-length book. You can search WorldCat for the author's name to see if a similar title appears. You can then see if we have the title here at Furman or via PASCAL Delivers.