@misc{_Wehrkreis_[1941],
 copyright={Public Domain},
 address={[Posen]},
 howpublished={online},
 year={[1941]},
 publisher={[wydawca nieznany]},
 language={ger},
 title={Wehrkreis XXI (Reichsgau Wartheland) : Gewässerkarte},
 type={Image},
 URL={http://www.rcin.org.pl/igipz/Content/218486/PDF/WA51_225742_PAND2199-3-r1941_Wehrkreis-XXI-Gewasserkar_0001.pdf},
 keywords={hydrographic maps, hydrography, Poland, Wartheland},
}