@misc{_M_[1940], copyright={Public Domain}, address={Gotha}, journal={Vogels Karte von Mitteleuropa. Fliegerkarte}, howpublished={online}, year={[1940]}, publisher={Justus Perthes}, language={ger}, title={M 32-NO Kassel}, type={Image}, URL={http://www.rcin.org.pl/igipz/Content/210106/PDF/WA51_190994_PTGC61-13-r1940_M-32-NO-Kassel_0001.pdf}, keywords={topographic maps, aerial maps, Kassel (Germany; region)}, }