Karte der Weichsel-Nogat-Linie
<a href="https://de.wikipedia.org/wiki/User:Chumwa" class="extiw" title="de:User:Chumwa">Maximilian Dörrbecker</a> (<a href="https://de.wikipedia.org/wiki/User:Chumwa" class="extiw" title="de:User:Chumwa">Chumwa</a>)
CC BY-SA 2.5
<span class="int-own-work" lang="en">Own work</span>, using <a href="//commons.wikimedia.org/wiki/File:MapOfWWIEasternFrontArea.svg" title="File:MapOfWWIEasternFrontArea.svg">this map</a> by <a href="//commons.wikimedia.org/wiki/User:Goran_tek-en" title="User:Goran tek-en">Goran tek-en</a>