Input (grade 11): From 1930-33 he taught at the Berlin Hochschule, from 1944 to 1958 at the Guildhall School of Music, and then at the Musikhochschule Köln (1957-82) and the Conservatory in Bern (1957-85).
Output (grade 10): From 1930-33 he taught at the Berlin Hochschule, from 1944 to 1958 at the Guildhall School of Music, London and then at the conservatory in Bern, Switzerland.