Do not try to reinvent the wheel. There are many useful guides out there that may help you jump start your research.
I agree with Anday Dorchack at Case Western Reserve that the "The goal of researching war crimes is the same as any legal research task: finding the best primary legal sources to help your client present her case in the best possible light. Secondary sources play a critical role in research the law of various international criminal tribunals, and well as public international law, and foreign law. When judging secondary sources, seek authoritativeness, comprehensiveness (if available), and currency".