When searching for books in Nimitz Library on the Panama Canal you will find there are various Call Number areas indicated:
E - U.S. History
F - History of Latin America
GB - Geography / Hydrology
HE - Social Sciences / Transportation
JX - Political Science / International Law
TC - Technology / Hydraulic Engineering
You can see the entire Library of Congress Classification Outline at this website: https://www.loc.gov/catdir/cpso/lcco/
Use WorldCat to search the catalogs of thousands of other libraries. If Nimitz Library doesn't have a title you need, use the Interlibrary Loan link above to request borrowing a copy.
Remember to check the footnotes or endnotes as well as the bibliography in any scholarly book you use. This often leads you to a variety of possible additional sources, including primary sources.