Annex to the Convention: Regulations respecting the laws and customs of war on land - Section I : On belligerents - Chapter II : Prisoners of war - Regulations: Art. 14.
Art. 14. An inquiry office for prisoners of war is instituted on the commencement of hostilities in each of the belligerent States, and, when necessary, in neutral countries which have received belligerents in their territory. It is the function of this office to reply to all inquiries about the prisoners. It receives from the various services concerned full information respecting internments arid transfers, releases on parole, exchanges, escapes, admissions into hospital, deaths, as well as other information necessary to enable it to make out and keep up to date an individual return for each prisoner of war. The office must state in this return the regimental number, name and surname, age, place of origin, rank, unit, wounds, date and place of capture, internment, wounding, and death, as well as any observations of a special character. The individual return shall be sent to the Government of the other belligerent after the conclusion of peace.
It is likewise the function of the inquiry office to receive and collect all objects of personal use, valuables, letters, etc., found on the field of battle or left by prisoners who have been released on parole, or exchanged, or who have escaped, or died in hospitals or ambulances, and to forward them to those concerned.