@misc{Regiomontanus_Joannes_Calendarium.,
 author={Regiomontanus Joannes},
 howpublished={online},
 publisher={Petr. Lichtenstein},
 language={lat},
 type={starodruki},
 title={Calendarium. Acc.: Jacobus Sentinus Ricinensius. In laudem operis Calendarii…carmina},
 keywords={stare druki Biblioteka PTPN, kalendarze},
}