@misc{Virdung_de_Hasfurt_Johann_Practica,
 author={Virdung de Hasfurt, Johann},
 howpublished={online},
 publisher={Kachelofen Konrad},
 language={lat},
 type={starodruk},
 title={Practica [Cracoviensis] ad a. 1491},
 keywords={Kraków 15w.},
}