تعریف تمبرهای غیرقانونی از نظر اتحادیه جهانی پست (UPU): “an illegal stamp is one that carries the name of a legitimate country or territory, but was not produced or printed by the postal administration of that country, and is not valid for postage anywhere in the world.” در بازار جهانی تمبر با تمبرهای غیر قانونی […]