Epistles of Gregory VII.; Baronius's Annals; Dupin's Ecclesiastical
history; Voigt, in his Hildebrand als Gregory VII.; Guizot's
Lectures on Civilization; Sir James Stephens's article on
Hildebrand, in Edinburgh Review; Dugdale's Mosasticon; Hallam's
Middle Ages; Digby's Ages of Faith; Jaffe's Regesta Pontificum
Romanorum; Mignet's series of articles on La Lutte des Papes contre
les Empereurs d'Allemagne; M. Villemain's Histoire de Gregoire
VII.; Bowden on the life and Times of Hildebrand; Milman's Latin
Christianity; Watterich's Romanorum Pontificum ab Aequalibus
Conscriptae; Platina's Lives of the Popes; Stubbs's Constitutional
History; Lee's History of Clerical Celibacy; Cardinal Newman's
Essays; Lecky's History of European Morals; Dr. Dollinger's Church
History; Neander's Church History; articles in Contemporary Review
of July and August, 1882, on the Turning Point of the Middle Ages.