@misc{Muhl_John_Adolf_(1879-1943)_Geschichte,
 author={Muhl, John Adolf (1879-1943)},
 howpublished={online},
 publisher={Marienwerder Westpr.},
 publisher={Wendt Groll},
 language={ger},
 type={książka},
 title={Geschichte des Rittergutes Herrengrebin},
 keywords={Żuławy Wiślane (Polska ; region), historia},
}