Liber Extra
In 1230 Gregory IX ordered St. Raymund of Pennafort to make a new collection, which is called the "Decretals of Gregory IX" ("Decretales Gregorii IX"). To this collection he gave force of law by the Bull "Rex pacificus", 5 September 1234. This collection is also known to canonists as the "Liber extra", i. e. extra Decretum Gratiani.