Serbia. (French-Hungarian Detachment in Zagreb). 1919. Picture post card of 'Belgrad, Serbia' addressed to France bearing Croatia Yvert 56, 10h red tied by 'Tresor et Postes'/ 526-D' date stamp with circular military cachet 'Armee Francaise de Hongrie/ Commissaire de Gare/ Zagreb' in violet. A wonderful item of military mail from the Forces in Zagreb.