11 January – Saint Hyginus

El Escorial, Real Biblioteca, Cod. Vitrinas 17, folio 4v
Hyginus, papa
Libro del Compendio della vita dei santi
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 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.

La vie des saints

Medieval Hagiography

BHL

Acta Sanctorum

The Cult of Saints in Late Antiquity Database

Liber pontificalis

Writings of Pope Hyginus

Documenta Catholica Omnia

Art & Architecture

Index of Medieval Art
– El Escorial, Real Biblioteca, Cod. Vitrinas 17, folio 4v: SANCTVS IGINVS EPISCOPVS DECIMVS VRBIS ROMAE A SANCTO PETRO (detail above)

Catalogo generale dei beni culturali

Portail Biblissima

South Wall of the Sistine Chapel
in situ
Die Sixtinische kapelle by Ernst Steinmann
see also
Post-Biblical Saints Art Index

11 January – Saint Theodosius

Menologion of Basil II (about)
Visoki Dečani Monastery
Compositions artistiques (about)
S. Théodose, abbé (St. Theodosius, Abbot), January 11th, 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
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 Sabine Baring-Gould.

Character Calendar

Pictorial Lives of the Saints

La vie des saints 

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.

Miniature Lives of the Saints for Every Day in the Year

The Lives of the Fathers of the Eastern Deserts by Richard Challoner.

Contemporary Hagiography

Acta Sanctorum

The Cult of Saints in Late Antiquity Database

Life of Saint Theodosius by Cyril of Scythopolis (free to borrow with registration).

Holy Land Topography

Kathisma (also)

The Monastery of Saint Theodosius

Art & Architecture

Index of Medieval Art

Portail Biblissima

Europeana

Blago Fund (search “Saint Theodosius”)

Monastery of St. Neophytos, Paphos, Cyprus (after 1197)

Medieval Religion Listserv – 2016 Dillon.

Post-Biblical Saints Art Index
Saints and their Attributes
Saints and their Emblems

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.

10 January – Blessed Gonsalvo of Amaranthia/Gundisalvus of Amarante

Saint Gonçalo of Amarante by António André in the Museum of Aveiro, Portugal (1618-1625, above)
Capela de São Gonçalo (Aveiro)
The Book of Saints

Modern Hagiography

Bibliotheca Sanctorum

Matyrologium Romanum

Lives of the Saints by Sabine Baring-Gould.

Short Lives of Dominican Saints

Stars in Saint Dominic’s Crown

Historical Tales and Legends by Miss Caddell.

Medieval Hagiography

Acta Sanctorum

Art & Architecture

Wikimedia Commons

Europeana

Warburg Institute Iconographic Database

Capela de São Gonçalo (Aveiro)

Wunder eines Dominikanerheiligen (hl. Gonzalo di Amarante?)

Saints and their Emblems