PLANCK, MAX. Autograph letter signed to Gustav Krupp von Bohlen und Halbach. Wangenheimerstr. 21, Berlin, May 18 1942. 2 pages, 8vo, holes punched at left, not affecting text, ink stamped and pencil marks by recipient. Planck is thanking Bohlen for his letter and regrets that he wasn't able to see him. He refers to his trip to Italy and wonders if it would be possible to see Bohlen and his wife in Berlin.