Lot no. 6308

POSTAGE-FREE OFFICIAL LETTERS OF THE LATVIAN POSTAL SERVICE: Sovjet postal stationery envelope disguised and used in Widrisch as registered cover, for sending in to the main post office in Riga the main portions of money transfers paid out), scarce Reference: "Lettland vor dem und als Teil vom Generalkommissariat OSTLAND", page 119, Harry von Hofmann (2001)