Annex to the Convention: Regulations respecting the laws and customs of war on land #Section III : Military authority over the territory of the hostile state - Regulations: Art. 52.
Art. 52. Requisitions in kind and services shall not be demanded from municipalities or inhabitants except for the needs of the army of occupation. They shall be in proportion to the resources of the country, and of such a nature as not to involve the inhabitants in the obligation of taking part in military operations against their own country.
Such requisitions and services shall only be demanded on the authority of the commander in the locality occupied.
Contributions in kind shall as far is possible be paid for in cash; if not, a receipt shall be given and the payment of the amount due shall be made as soon as possible.