Watch List notes:

Germany: early aviation B&W photographic picture postcard of biplane over the Alps, titled "Flugzeug über den Allgäuer Alpen von einem zweiten Flugzeug aufgenommen" (Airplane over the Allgäu Alps taken [photographed] by a second aircraft); published by Postkartenvertreib W. Sanke, Berlin; unused: near-mint on front, some age marks on back.