MLA

Bartolo, of Sassoferrato, 1313-1357. Tractatus minoricarum. Box. approximately 1450.. https://collections.library.yale.edu/catalog/32345781.

APA, 6th edition

Bartolo, of Sassoferrato, 1313-1357. (["Box"])(approximately 1450.)[Tractatus minoricarum]. https://collections.library.yale.edu/catalog/32345781.