One, or more, of the books Alexander Moritz Frey (March 29, 1881 to 1957), wrote were burned May 10, 1933 at a Nazi event. Frey got out of Germany that year .
Information on Frey is sparse, but a biography of Frey was reviewed by Der Spiegel in 2007 and gives us some information.
Frey, a pacifist, served as a medical assistant in the [same] regiment [as Hitler in World War I]. He once had to treat Hitler, and "gave him some sort of tablet to swallow." However Hitler ignored Frey's recommendation that he see a doctor -- so that he would gain the reputation among his comrades of someone who soldiered on despite being ill. "He made sure that ... it came to the ears of the officers that Hitler has a 'terrific throat infection' but is doing his duty nonetheless," Frey writes.
The book we would love to read, but is not easily found, Frey's The Stout-Hearted Cat, was translated into English in 1947, possibly the same year it was written. (Worldcat for once seems to have gaps). We do know the book is often listed as juvenile fiction, but that is not the right category. This emendation appeared in Kirkus Reviews:
Apologies for reporting this (page 336) as a juvenile. But-though we thought it odd as a book for children, we think it odder as a book for adults. It's not quite fantasy, certainly not in its symbolism. Rather is it a fairy tale, in the story of a very human white cat belonging to an old woman in Central Europe, and of the cat's devotion to the son whose death the mother would not accept and who returned from ....too late to see his mother. Adventures and misadventures, with a ""happy ending"" for an absurd and not a bit funny story. This is no Stuart Little, though there seems to be a far-fetched effort to achieve the same effect.
The Stout-Hearted Cat was translated by Richard and Clara Winston. Hans Fischer did the drawings, one of which is below.
Alexander Frey was born in Munich and died in Zurich.