ICRC databases on international humanitarian law
Treaties and Documents
1949 Conventions and Additional Protocols, and their Commentaries
Historical Treaties and Documents
Convention (IV) respecting the Laws and Customs of War on Land and its annex: Regulations concerning the Laws and Customs of War on Land. The Hague, 18 October 1907.
Annex to the Convention: Regulations respecting the laws and customs of war on land - Section II : Hostilities - Chapter I : Means of injuring the enemy, sieges, and bombardments - Regulations: Art. 26.
Art. 26. The officer in command of an attacking force must, before commencing a bombardment, except in cases of assault, do all in his power to warn the authorities.