Heinrich Hoffmann and Peter Kaltenbach) C. Plath (F.W. Schaafhausen books & textbook
C. Plath, 1862-1962; part 1: The history of the firm of C. Plath (Schaafhausen); part 2: The development of the sextant (Hoffmann and Kaltenbach)
Heinrich Hoffmann and Peter Kaltenbach) C. Plath (F.W. Schaafhausen
Verlag Hanseatischer Merkur, [ /1962T Hardcover
