Note 433:1 — Chapter XVIII · PREPARATIONS FOR THE HILDEBRANDINE REFORMATION
Reading edition
Migne, vol. 144, p. 145; Vagler, Peter Damiani; Neukirch, Das Leben des Peter Damiani; Neander, iii., 382, 397; Hefele, iv.; Cooper, Flagellation and the Flagellants; Schaff, iv., 787.