Vintage postcard photograph of the Ukrainian-born conductor, a composition student of Schreker who went on to be Furtwängler's assistant in Berlin until the rise of the Nazis forced him to leave for the United States. Specialist in Mahler and Bruckner, he was a champion of 20th century music but had a vast and varied repertory and a long and spectacular career. Boldly signed in blue ink in the upper blank margin. 9 x 14 cm. Very fine.