@misc{Krollmann_Christian_Der,
 author={Krollmann, Christian},
 howpublished={online},
 publisher={Preussenverlag},
 language={ger},
 title={Der Deutsche Orden in Preußen},
 type={książka},
 keywords={Prusy - historia, Krollmann, Christian (1866-1944), Krzyżacy - historia},
}