MLA

Petrus, Comestor, active 12th century. Historia scholastica, etc. [between 1200 and 1210; 1300 and 1350]. https://collections.library.yale.edu/catalog/10269864.

APA, 6th edition

Petrus, Comestor, active 12th century. ([between 1200 and 1210; 1300 and 1350])[Historia scholastica, etc]. https://collections.library.yale.edu/catalog/10269864.