20 Pfg St. Maryãs Church (2) in mixed franking with 10 Pfg St. Maryãs Church (4) reverse on correctly franked special delivery letter from GELSENKIRCHEN BUER 1 15.2.52 to Cologne Lindenthal with arrival stamp from 15.2.52, as usual traces should by of this rarity not disturb, cover with opening deficiency, photo expertize Schlegel BPP "the cover was over the postal route transported, correctly franked franked. ", rarity! - in this kind probably the only one exists! (former starting price 900)