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.
Sieges and bombardments - Art. 17.
Art. 17. In such cases all necessary steps must be taken to spare, as far as possible, buildings dedicated to art, science, or charitable purposes, hospitals, and places where the sick and wounded are collected provided they are not being used at the time for military purposes.
It is the duty of the besieged to indicate the presence of such buildings by distinctive and visible signs to be communicated to the enemy beforehand