@misc{Gratian_(11..?-1160?)_Decretum,,
 author={Gratian (11..?-1160?)},
 howpublished={online},
 publisher={Georgius Arrivabene},
 language={lat},
 type={inkunabuł},
 title={Decretum, cum apparatu Bartholomaei Brixiensis et Ioannis Semecae (Teutonici)},
}