50 C. Special stamp \"Musica\" in conjunction with horizontal pair 25 C. Postal stamp \"Merkur head\" with in each case horizontal overprint, tariff right on clean letter with first day postmark \"DUNKERQIE 1 - 7 40\" to Arnecke with arrival postmark on the back from 3.7.40. Photo expertize Gerhard Krischke: \"the condition is perfect. \", First-Day-Covers with stamps from public ownership are rarely offered!