23 April – Saint Adalbert of Prague

Gniezno Doors

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.

Victories of the Martyrs by Saint Alphonsus Liguori. 

Tradition in Action

Medieval Hagiography

BHL, Supplement

Acta Sanctorum

Writings of Saint Adalbert

Documenta Catholica Omnia

Art & Architecture

Index of Medieval Art

Europeana

A Guide to Christian Iconography: Images, Symbols, and Texts

Gnienzo Doors

Painted Panels with Saint Procopius – 14C & 15C

19C Baptism of Vajk

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

Caractéristiques des saints dans l’art populaire by Charles Cahier – aigle, Baptême, doigt, lance, massue, rame, tronc (torse) mutilé.

Legends of the Monastic Orders as Represented in the Fine Arts by Mrs. Jameson.

Lives and Legends of the English Bishops and Kings, Mediaeval Monks, and Other Later Saints by Mrs. Arthur Bell.

Saints and their Symbols: A Companion in the Churches and Picture Galleries of Europe by E. A. Greene.

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

Music

Cantus: A Database for Latin Ecclesiastical Chant

22 April – Saint Theodore of Sykeon

Annus Dierum Sanctorum
Legem ponebat aquis, et viam procellis sonantibus.
He gave a law for the waters, and a way for the sounding storms.
Job 28.26
Benedicite fulgura et nubes Domino.
O ye lightnings and clouds, bless the Lord.
Daniel 3.73
Benedicite flumina Domino.
O ye rivers, bless the Lord.
Daniel 3.78

Modern Hagiography

Bibliotheca Sanctorum

Martyrologium Romanum

Roman Martyrology

Lives of the Saints by Alban Butler.

Medieval Hagiography

BHL

Acta Sanctorum

The Life of St. Theodore of Sykeon

Art & Architecture

Index of Medieval Art

Warburg Institute Iconographic Database

Saints and their Emblems

22 April – Saint Opportuna

Modern Hagiography

Bibliotheca Sanctorum

Martyrologium Romanum

Dictionary of Saintly Women

Book of Saints by Alban Butler.

Medieval Hagiography

BHL

Acta Sanctorum

La vie de sainte Opportune, abbesse d’Almenêches au diocèse de Séez en Normandie, poème legendaire du moyen-âge, publié pour la première fois avec une introduction et des notes

Art & Architecture

Index of Medieval Art

POP : la plateforme ouverte du patrimoine
including Sainte Opportune, saint Julien de Brioude

Saints and their Attributes
Saints and their Emblems

Caractéristiques des saints dans l’art populaire by Charles Cahier – allegories, ange, coeur, eau, groupe.

Lives and Legends of the English Bishops and Kings, Mediaeval Monks, and Other Later Saints by Mrs. Arthur Bell.

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

Cantus: A Database for Latin Ecclesiastical Chant

Customs & Devotions

Late Medieval French Prayers