The Library of Congress Classification System is used to organize books on the shelves, using 21 categories, labeled A-Z.
B--Philosophy, Psychology, Religion
C--Auxiliary Sciences of History
D--History: General & Outside the Americas
F--History: United States Local & America
The next step in your research process is to find a book on your chosen controversial topic. The library has several special series of books exclusively on controversial issues (Opposing Viewpoints, Current Controversies, At Issue, Contemporary Issues, Information Plus, Point Counterpoint, Taking Sides). These specialized books contain essays either for or against an issue, and they contain factual data to help support their argument.