@misc{_N_[1942],
 copyright={Public Domain},
 address={Gotha},
 journal={Vogels Karte von Mitteleuropa. Fliegerkarte},
 howpublished={online},
 year={[1942]},
 publisher={Justus Perthes},
 language={ger},
 title={N 32 - NW Tondern},
 type={Image},
 URL={http://rcin.org.pl/Content/210096/PDF/WA51_190721_PTGC61-1-r1942_N-32-NW-Tondern_0001.pdf},
 keywords={topographic maps, aerial maps, Helgoland (Germany; island), North Frisian Islands},
}