John Philip SOUSA (1854-1932). P.S.; illustrated postcard. Postcard from the Tour der Amerikanischen Militarkapelle, with 60 artists led by John Philip Sousa. Under his portrait, and between two photos of him conducting, he signed: "John Philip Sousa"; under his signature, that of pianist Emil von SAUER (1862-1942), who was a pupil of Liszt.