Willi Sanke published a series of about 600-700 numbered postcards, showing World War I aviators circa 1910 - 1918/20. He was based in Berlin and his cards were often issued under the name of Postkartenvertrieb W. Sanke (Post Card Distribution W. Sanke).[1][2][3] On some of these postcards, the photographers are identified: for example, Fritz Fischer, Nicola Perscheid (1864–1930)[4], and Alfred Krauth.