S23736

Chicago flight 1933 - registered letter with high valuable Switzerland airmail stamps franking (the 90 Cent stamp  in a spectacular blk. of 4 stamps), cancelled Romanshorn 14.X.33 sent via Friedrichshafen and carried by airship to Chicago (arrival postmark), sent bak via new York to Switzerland (postmarks backside), very good quality, Sieger 238 CH, Michel Zeppelin specialized catalogue 352 a CH