they say "Northrop Aircraft Inc" on each of the frames in the blue prints they are numbered here is a closer up photo of one of the frames its a clear as i could possibly get it, I will not know if its complete until i can view them.
Thank you to everyone, since it seems that any of the actual photos from Mr. Nowarra's collection of WWII seems to be unheard of, well that makes them priceless to me, after a special request from a professor of mine I have decided to donate the photos to my school.
these are the actual prints they are stamped in purple looking ink on the back saying "Reproduction forbidden without permission by Heinz J. Nowarra Berlin-Ltd., Weddegenweg"