Liber Extra
The decretals of the successors of Gregory IX were also arranged in collections, of which several were official, notably those of popes Innocent IV, Gregory X and Nicholas III, who ordered their decretals to be inserted among those of Gregory IX. In addition to these, several unofficial collections were drawn up. The inconveniences which Gregory IX had wished to remedy presented themselves again. For this reason, Boniface VIII made a new collection of decretals which he promulgated by the Papal Bull "Sacrosanctæ" of 3 March 1298. This is the "Sextus Liber Decretalium"; it has a value similar to that of the Decretals of Gregory IX. Boniface VIII abrogated all the decretals of the popes subsequent to the appearance of the Decretals of Gregory IX which were not included or maintained in force by the new collection; but as this collection later than that of Gregory IX, it modifies those decisions of the latter collection which are irreconcilable with its own.