Modern Hagiography
Lives of the Saints by Alban Butler.
Lives of the Saints by Sabine Baring-Gould.
The Liturgical Year by Dom Guéranger.
Victories of the Martyrs by Saint Alphonsus Liguori.
Our Birthday Bouquet Culled from the Shrines of the Saints and the Gardens of the Poets by Eleanor C. Donnelly.
The Lives of Saints, with Other Feasts of the Year, According to the Roman Calendar by Peter Ribadeneira.
Medieval Hagiography
The Golden Legend (and illustrations)
Breviarium Romanum – Latin & English.
Art & Architecture
Index of Medieval Art – John of Rome, Paul of Rome
Warburg Institute Iconographic Database
Medieval Religion Listserv – 2016 Dillon.
martirio dei Santi Paolo e Giovanni & elemosina dei Santi Giovanni e Paolo
Santi Giovanni e Paolo, Venice
Martyrdom in Santo Stefano Rotondo in Rome
Sacred and Legendary Art volume II by Mrs. Jameson.
A Handbook of Christian Symbols and Stories of the Saints as Illustrated in Art by Clara Erskine Clement.
Saints and their Symbols: A Companion in the Churches and Picture Galleries of Europe by E. A. Greene.
Music
Nihil sub sole novum 
