This page presents a list of specialized subject encyclopedias. These are an excellent starting point for research. Articles include background information, identify issues, and provide selected bibliographies that list other sources recommended by an expert in the field.
When you are beginning work on an unfamiliar subject, consider using a published bibliography. Use the bibliography in your textbook, use the bibliography in the back of books you find in Primo, or use a separately published bibliography, such as the American Historical Association's Guide to Historical Literature.
Your professor may have told you not to use encyclopedias as sources for your projects. It is true that general encyclopedias such as Wikipedia or Britannica are usually not considered appropriate sources for research papers. Subject encyclopedias are different: the articles are written by experts on the subject selected because of their specific expertise. The articles provide the background information you will need to begin your subject as well as short bibliographies of important works recommended by the author. This is just a selection of some of the more general subject encyclopedias.