Modern Hagiography
Lives of the Saints by Alban Butler.
Lives of the Saints by Sabine Baring-Gould.
The Liturgical Year by Dom Guéranger.
An Alphabet of Saints by Robert Hugh Benson, Reginald Balfour, and Charles Ritchie.
Victories of the Martyrs by Saint Alphonsus Liguori.
Legends of the Blessed Sacrament Gathered from the History of the Church and the Lives of the Saints by Emily Mary Shapcote.
Medieval Hagiography
Inscription at Tomb written by Pope Damasus (Carmen X)
The Golden Legend (and illustrations)
Writings by Pope Sixtus II
Art & Architecture
Cappella Niccolina, Palazzi Pontifici, Vatican painted by Fra Angelico (see also)
Portrait in the Sistine Chapel by Sandro Botticelli (try to find in situ)