23 December – Saint Victoria of Tivoli

Le Martyre de sainte Victoire
Compositions artistiques (about)
Ste. Victoire, vierge et martyre (St. Victoria, Virgin and Martyr), December 23rd, from Les Images De Tous Les Saincts et Saintes de L'Année (Images of All of the Saints and Religious Events of the Year), Jacques Callot (French, Nancy 1592–1635 Nancy), Etching; second state of two (Lieure)
Les Images De Tous Les Saincts et Saintes de L’Année
Libro del Compendio della Vita di tutti Santi
The Book of Saints

Modern Hagiography

Bibliotheca Sanctorum

Roman Martyrology

Sanctorale Catholicum

Dictionary of Saintly Women

Lives of the Saints by Alban Butler.

Lives of the Saints by Francis Weninger.

Lives of the Saints by Sabine Baring-Gould.

Our Birthday Bouquet Culled from the Shrines of the Saints and the Gardens of the Poets by Eleanor C. Donnelly.

Pictorial Half Hours with the Saints by Auguste François Lecanu.

La vie des saints

Medieval Hagiography

BHL, Supplement

The Cult of Saints in Late Antiquity Database

Art & Architecture

Index of Medieval Art

Catalogo generale dei beni culturali

BeWeB

Wikimedia Commons

Sanctuary of Santa Vittoria in Monteleone Sabino (her life here turns legendary).

Post-Biblical Saints Art Index
Saints and their Emblems

Music

Cantus: A Database for Latin Ecclesiastical Chant

23 December – Saint Servulus

View of Fresco of The Death of Saint Servolo in San Clemente in Rome (about and black and white photo, blurry color photos linked to below)
S. Survule, le paralytique (St. Survulus, the paralytic), December 23rd, from Les Images De Tous Les Saincts et Saintes de L'Année (Images of All of the Saints and Religious Events of the Year), Jacques Callot (French, Nancy 1592–1635 Nancy), Etching; second state of two (Lieure)
Les Images De Tous Les Saincts et Saintes de L’Année
Libro Compendio della vita di tutti i santi
Annus Dierum Sanctorum
Vir, qui erat Claudus, quem ponebant quotidie ad portam templi, ut peteret eleemosynam ab introeuntibus in templum.
A man who was lame, whom they laid every day at the gate of the temple, that he might ask alms of them that went into the temple.
Acts 3.2
The Book of Saints

Modern Hagiography

Bibliotheca Sanctorum

Martyrologium Romanum

Roman Martyrology

Sanctorale Catholicum

Lives of the Saints by Alban Butler.

Lives of the Saints by Francis Weninger.

Lives of the Saints by Sabine Baring-Gould.

Character Calendar 

Pictorial Lives of the Saints 

La vie des saints 

Anecdotes and Incidents: Ecclesiastical and Religious.

Contemporary Hagiography

BHL

Pope Gregory the Great spoke about Saint Servulus in his homily on the Parable of the Sower (Luke 8.4-15).  He also wrote about him in his Dialogues.

Art & Architecture

Catalogo generale dei beni culturali

BeWeB

Death of San Servolo by Tommaso Chiari (info here and here)

Guide to Christian Iconography: Images, Symbols, and Texts

Saints and their Emblems

Emblems of Saints by Which They Are Distinguished in Works of Art by F. C. Husenbeth.