ICRC databases on international humanitarian law
Treaties, States Parties and Commentaries
Treaties and Documents
Geneva Conventions of 1949 and Additional Protocols, and their Commentaries
Historical Treaties and Documents
Project of an International Declaration concerning the Laws and Customs of War. Brussels, 27 August 1874.
Spies - Art. 20.
Art. 20. A spy taken in the act shall be tried and treated according to the laws in force in the army which captures him.