Purgatory: Explained by the Lives and Legends of the Saints Rev. Fr. F. X. Schouppe, S.J.
You would never dream so much is known about Purgatory. Not only is the basic teaching of the Church given here, but also countless true stories of apparitions and revelations on Purgatory from the lives of St. Margaret Mary, St. Gertrude, St. Bridget of Sweden, the Cure of Ars, St. Lidwina of Schiedam, etc.