Feldberg Mulhouse, 25 Pfg airmail stamp, corner fault, a little patina, as usual traces, with centric clear flight special cancel \"first airmail. 11.9.1913\" on photo postcard of the pilots Artur Faller before his flight apparatus and on face autograph full signature, with 5 Pfg Germania from Mulhouse 18.9.13 to Bad Nauheim, alongside hotel cancel \"Feldbergerhof . \", short greeting text, expertized Grabowski BPP