Hi,
On the very slight chance I might possibly have one or two books that Dan doesn't, I thought I'd present some German bookcover art from the '30's:
Werner Chomton was, if I'm not mistaken, a German two-seater veteran of the war who not only authored this book loosely based on his experiences but also painted the cover and illustrated it with his own pen and ink sketches. He became sort of the go-to guy for aviation illustration for several other books, such as Hermann Kohl's biography of MvR.