Essentials of international law : an Australian context by
Essentials of International Law: An Australian Context provides a comprehensive guide to the basic rules and sources of international law. Designed as a concise and accessible reference for both students and practitioners, it offers Australia-specific examples to contextualise international law concepts for Australian readers. Key principles, cases, legislation, treaties and other international instruments are identified and explained succinctly.
Both Oxford androutledge publish a series of handbooks on different areas of international law.
For example:
The Oxford Handbook of Jurisdiction in International Law by 
Research Handbook on Territorial Disputes in International Law by Use the Library catalogue to find other handbooks in these series.
International Legal Research in a Global Community by 
International Legal Research in a Nutshell by 
The Oxford Handbook of the Sources of International Law by 
Formalism and the Sources of International Law by 