Modern Hagiography
Lives of the Saints by Alban Butler.
Lives of the Saints by Francis Weninger.
Lives of the Saints by Sabine Baring-Gould.
The Liturgical Year by Dom Guéranger.
The Lives of Saints, with Other Feasts of the Year, According to the Roman Calendar by Peter Ribadeneira.
Medieval Hagiography
The Cult of Saints in Late Antiquity Database
Art & Architecture
Index of Medieval Art
especially Carolinian apse mosaic
Catalogo generale dei beni culturali
The church of Santa Susanna 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.
The Saints in Art by Joseph Maria von Radowitz.
Emblems of Saints by Which They Are Distinguished in Works of Art by F. C. Husenbeth.
Music
Nihil sub sole novum 
