@misc{Petry_Wilhelm_Die,
 author={Petry, Wilhelm and (1883-1936) and Autor},
 howpublished={online},
 publisher={Verlag von Konrad Wittwer},
 language={niemiecki},
 title={Die Baukontrolle im Eisenbetonbau},
 type={książka},
 keywords={beton zbrojony},
}