"Et hoc secundo modo posset Papa esse schismaticus, si nollet tenere cum toto Ecclesiae corpore unionem et coniunctionem quam debet, ut si tentat et totem Ecclesiam excommunicare, aut si vellet omnes Ecclesiasticas caeremonias apostolica traditione firmatas evertere. (De Charitate, Disputatio XII de Schismate, sectio 1)
"And in this second way the Pope could be schismatic, if he were unwilling to be in normal union with the whole body of the Church, as would occur if he attempted to excommunicate the whole Church, or, as both Cajetan and Torquemada observe, if he wished to overturn the rites of the Church based on Apostolic Tradition."
"Si quis dixerit, receptos et approbatos ecclesiae catholicae ritus in solemni sacramentorum administratione adhiberi consuetos aut contemni, aut sine peccato a ministris pro libito omitti, aut in novus alio per quemcumque ecclesiarum pastorem mutari posse: anathema sit." - -Session VII, Canon 13
"If anyone says that the received and approved rites of the Catholic Church, accustomed to be used in the administration of the Sacraments, may be despised or omitted by the ministers without sin and at their pleasure, or may be changed by any pastor [which includes the Supreme Pastor, the Pope] of the churches to other new ones, let him be anathema."