For basic principles, start with these law school study guides.
Public International Law in a Nutshell, 6th ed. by 
International Law Frameworks, 4th ed. by 
Understanding International Law, 3rd ed. by 
International Law: Examples and Explanations, 2d ed. by 
Principles of International Law 3rd Edition by Consult these books for more in-depth, scholarly overviews of international law. Several of these authors — especially Brownlie, Oppenhiem, and Brierly — would be considered to be among "the most highly qualified publicists."
Brownlie's Principles of Public International Law, 8th ed. by 
Oppenheim’s International Law, 9th ed. by 
Brierly's Law of Nations: An Introduction to the Role of International Law in International Relations by 
Public International Law, 5th edition by 
Public International Law: Contemporary Principles and Perspectives by 
International Law by 
International Law, 5th ed. by 
Law Among Nations: An Introduction to Public International Law, 11th ed. by 
Handbook of International Law, 2nd ed by 
Akehurst's Modern Introduction to International Law, 8th rev. ed. by 
A Manual of International Law, 6th ed. by 
Bowett's Law of International Institutions, 6th ed. by General Principles of Law: As Applied by International Courts and Tribunals by Oxford University Press's "OSAIL" (Oxford Scholarly Authorities in International Law) includes the full text of more that 50 important books dealing with various aspects of international law.
Questions of whether a state will be held responsible for acts it commits are present in virtually every international law dispute. The draft articles on the Responsibility of States for Internationally Wrongful Acts from the International Law Commission should be among the first stops for researchers exploring issues of state responsibility.
Restatement of the Law, the Foreign Relations Law of the United States by A rich collection of books and other materials from HeinOnline.
To find scholarly, book-length topical discussions dealing with international law at USF, use Ignacio.
Ignacio searches broad descriptions of books. For good results try keyword searches following this model:
"topic words" international law
"topic words" "international law"
For example:
humanitarian "international law"
"armed conflict" international law
To further refine your search, select "Law Stacks" from the "Location" options on the left-hand side of the screen.
The Peace Palace Library serves Hague institutions such as the International Court of Justice, the Permanent Court of Arbitration, and the Hague Academy of International Law, as well as international law scholars from around the world.
Its catalog has been customized for international law research and is a great way to find citations to relevant books — book chapters.
Once you know of a useful book (or a chapter in a book), use Ignacio or WorldCat to locate a copy you can use, or ask about an interlibrary loan.
To find scholarly books worldwide, try WorldCat.
WorldCat searches broad descriptions of books. For good results, try keyword searches following this model:
"topic words" international law
For example:
humanitarian international law
"armed conflict" international law
Find books by searching the full text of books using Google Books.
Because Google Books searches the full text, you can often get good results with more narrow, specific searches than would be useful in Doncore or WorldCat — searches such as:
"non state actors" terrorism international law
"state succession" treaties "international law"
