Ernst Schertel
Ernst Schertel (20 June 1884 – 30 January 1958) was a German author, probably best known for his 1923 Magic: History, Theory and Practice. He had an "astonishingly diverse career" including running an eight-member dance troupe, Traumbuehne Schertel, active from 1925 to 1927. From 1927 to 1931 Schertel edited ASA – Das Magazin für Körper, Kunst und neues Leben.
Schertel's Magic: History, Theory and Practice was found to be one of the most-heavily annotated books in Adolf Hitler's personal library. "Hitler’s extensive markings (sixty-six in all) in his copy of Magic were in the form of vertical lines in the margins."