ICRC – Rules of War (In A Nutshell) & What Is International Humanitarian Law?
https://www.youtube.com/watch?v=HwpzzAefx9M and see https://www.icrc.org/en/war-and-law/ihl-other-legal-regmies and see https://www.icrc.org/eng/assets/files/other/what_is_ihl.pdf and see https://www.icrc.org/customary-ihl/eng/docs/v1 and see http://www.defense.gov/Portals/1/Documents/pubs/Law-of-War-Manual-June-2015.pdf