This is from the edition of Gratian's Decretum printed in 1471 in Strassburg. It is one of the oldest printed books in our collection, and one of the largest. The Decretum is considered one of the most important texts in canon law. Originally authored by a jurist named Gratian in the 1100s, the book is a teaching text as well as a collection of laws. Gratian's original text is surrounded by the gloss added by later teachers and commentators. See the online catalog record at http://morris.law.yale.edu/record=b453872~S3a%22.