Incipit - O
- O ()
- O Jesu! (Solesmes)
- O mysterium! (Solesmes)
- O Sena! (Solesmes)
- O admirabile commercium (Dominican)
- O admirabile commercium (Solesmes 2000s)
- O admirabile commercium (Solesmes 1961)
- O admirabile commercium (Solesmes 1934)
- O admirabile commercium (Solesmes)
- O admirabile commercium (Verona)
- O admirabile commercium (alleluia) (Solesmes 1934)
- O admirabile gaudium (Venetian)
- O Adonai (Verona)
- O Adonai (Solesmes)
- O Adonai (Solesmes)
- O Adonai (Dominican)
- O Adonai (Solesmes 1961)
- O Adonai (Solesmes 2000s)
- O Adonai (Solesmes 1934)
- O aeterne Deus (J. Schmidt-Gorg 1969 ed.)
- Obaudite me (Dominican)
- Obaudite me (Solesmes)
- Obaudite me (Dominican)
- O beata Catharina! (Solesmes)
- O beata Agnes (Dominican)
- O beata anima (Solesmes 1934)
- O beata Caecilia (Sandhofe)
- O beata Caecilia (Dominican)
- O beatae passionis (Solesmes 2000s)
- O beata et benedicta (Dominican)
- O beata infantia (Solesmes 1957)
- O beata Margarita (Dominican)
- O beata Mater (Solesmes)
- O beata Virgo (Solesmes)
- O beate Jacobe (Dominican)
- O beate Stanislae (Proprium Poloniae)
- O beatum Apostolum (Solesmes)
- O beatum Pontificem (Solesmes 1961)
- O beatum Pontificem (Solesmes 1934)
- O beatum pontificem (Dominican)
- O beatum Pontificem qui totis (Solesmes)
- O beatum virum cujus (Solesmes)
- O beatum virum cujus anima (Solesmes 1961)
- O beatum virum cujus anima (Dominican)
- O beatum virum cujus anima (Solesmes 1934)
- O Beatum virum in cujus (Sandhofe)
- O beatum virum in cujus (Solesmes 1957)
- O beatum virum Martinum (Sandhofe)
- O Beatum virum qui spreto (Solesmes 1934)
- Obedientiae pennis (Solesmes 1934)
- Oblatus est (Solesmes 1934)
- Oblatus est (Verona)
- Oblatus est (Dominican)
- Oblatus est (Solesmes)
- Obliti sunt Deum (Nocturnale Vaticanum)
- Obliti sunt Deum (Sandhofe)
- O bona crux (Dominican (Jandel))
- O bona crux (Sandhofe)
- O bone Jesu (Dominican)
- Obsecro Domine (Sandhofe)
- Obsecro Domine aufer (Solesmes 1961)
- Obsecro Domine aufer (Solesmes)
- Obsecro Domine memento (Solesmes 1961)
- Obsecro Domine memento (Solesmes 1934)
- Obsecro Domine memento (Solesmes)
- Obsecro Domine (Resp.) (Gregofacsimil)
- Obsecro te Azaria (Sandhofe)
- Observa fili (Solesmes 1934)
- Observa fili (Solesmes 1961)
- Observa fili praecepta (Solesmes)
- Obtulerunt (Palmer & Burgess)
- Obtulerunt (Sandhofe)
- Obtulerunt (Solesmes)
- Obtulerunt Discipuli ()
- Obtulerunt discipuli (Verona)
- Obtulerunt discipuli (Solesmes 2000s)
- Obtulerunt discipuli (Solesmes)
- Obtulerunt discipuli Domino (Solesmes 1934)
- Obtulerunt pro eo (Solesmes)
- Obtulerunt pro eo (Dominican)
- Obtulerunt pro eo (Ant.) (Solesmes 1961)
- Obtulerunt pro eo Domino (Simplex)
- Obtulerunt pro eo Domino (Solesmes 2000s)
- Obtulerunt pro eo Domino (Solesmes 1934)
- Obviam sacratissimis pignoribus (Solesmes 1935)
- O Caelestis norma vitae (Solesmes 1934)
- O Caelestis norma vitae (Solesmes 1934)
- O Caelestis norma vitae (Solesmes 1934)
- O Caelestis norma vitae (Solesmes 1934)
- O Caput cruentatum (Vatican)
- O castitatis signifer (Solesmes 1983)
- O Catharina nobilis! (Solesmes)
- Occidit Herodes (Solesmes 2000s)
- Occurrunt turbae (Solesmes)
- Occurrunt turbae (Vatican)
- Occurrunt turbae (Palmer & Burgess)
- Occurunt turbae (Dominican)
- O certe praecipuus (Dominican)
- O Christe robur Martyrum (Proprium Poloniae)
- O Christi pietas (Dominican)
- O Christi sponsa (Dominican)
- O Clavis (Dominican)
- O Clavis David (Solesmes 1961)
- O Clavis David (Verona)
- O Clavis David (Solesmes 2000s)
- O clavis David (Dominican)
- O clavis David (Solesmes)
- O clavis David (Solesmes)
- O clavis David et sceptrum (Solesmes 1934)
- O cor amoris victima (Solesmes)
- O Crucis victoria (Sandhofe)
- O Crucis victoria (Nocturnale Vaticanum)
- O crux admirabilis (Dominican)
- O crux admirabilis (Solesmes 2000s)
- O crux benedicta quae (Solesmes 1961)
- O crux benedicta quae (Solesmes 1934)
- O crux benedicta quae (Dominican)
- O Crux benedicta quae sola (Solesmes)
- O crux benedicta quia (Dominican)
- O Crux fructex salvificus! (Solesmes)
- O Crux gloriosa (gregofacsimil)
- O crux gloriosa (Solesmes)
- O Crux splendidior (Solesmes 1934)
- O Crux splendidior (Solesmes)
- O crux splendidior (Dominican)
- O crux splendidior (Solesmes 1961)
- O Crux venerabilis (Sandhofe)
- O Crux venerabilis (Nocturnale Vaticanum)
- Oculi Domini super metuentes (Solesmes 1934)
- Oculi mei (Simplex)
- Oculi mei (Palmer & Burgess)
- Oculi mei (Dominican)
- Oculi mei (Vatican)
- Oculi mei (Solesmes 1981)
- Oculi mei (Cisterciensis 1955)
- Oculi mei (Verona)
- Oculi mei (Solesmes)
- Oculi Omnium (English Adaptation)
- Oculi omnium (Vatican)
- Oculi omnium (Solesmes)
- Oculi omnium (Nivers)
- Oculi omnium (Chants Abreges)
- Oculi omnium (Triplex)
- Oculi omnium (Dominican)
- Oculi omnium (Palmer & Burgess)
- Oculis ac manibus (Dominican)
- Oculis ac manibus (Sandhofe)
- Oculis ac manibus (Solesmes 1961)
- Oculis ac manibus (Solesmes)
- Oculis ac manibus (Solesmes 1934)
- Oculus Dei (Solesmes)
- Oculus Dei (Vatican)
- Oculus Dei (Solesmes)
- O decus Ecclesiae (Dominican)
- O diem gemma ()
- O dignissima Christi sponsa (Solesmes 1934)
- O Dio ()
- O Doctor optime (Solesmes 1961)
- O Doctor optime (Solesmes 1934)
- O doctor optime (Dominican)
- O Doctor optime(Athanasi) (Solesmes 1934)
- O Doctor optime (nomina doctorum) (Solesmes 1934)
- O Domine (Solesmes 1934)
- O Domine... ego servus (Solesmes)
- O Domine... et filius (Solesmes)
- O Domine salvum me (Solesmes)
- O Domine salvum me fac (Verona)
- Odor tuus (Solesmes 2000s)
- Odor vestimentorum (S. Rita) (Solesmes 1961)
- O Emmanuel (Solesmes)
- O Emmanuel (Solesmes 1961)
- O Emmanuel (Solesmes)
- O Emmanuel (Dominican)
- O Emmanuel (Solesmes 2000s)
- O Emmanuel (Verona)
- O esca viatorum (Basse)
- O esca viatorum (Polyphonique)
- O esca viatorum (Tenor)
- O felicem virum (Solesmes 1957)
- O felix felicis (Dominican)
- Offerentur Regi virgines (Sandhofe)
- Offerte vobis pacem (Solesmes)
- O filii et filiae (Polish)
- O filii et filiae (Solesmes)
- O filii et filiae (Annamitice)
- O filii et filiae II (Annamitice)
- O filii et filiae III (Annamitice)
- O filii et filiae IV (Annamitice)
- O florem Eden (Proprium Poloniae)
- O frondens virga (J. Schmidt-Gorg 1969 ed.)
- O gente felix (Dominican)
- O gente felix hospita (Solesmes)
- O gloriosa Dei Genitrix (Solesmes 1957)
- O gloriosa Domina (Solesmes 1934)
- O gloriosa Domina (Cistercian)
- O gloriosa domina (Solesmes 1983)
- O gloriosa Virginum (Vatican)
- O gloriosa Virginum (Vatican)
- O gloriosa virginum (Annamitice)
- O gloriosa virginum (Solesmes 1961)
- O gloriosa Virginum Regina formosissima (Proprium Poloniae)
- O gloriosi Apostoli (Solesmes 1957)
- O Heros ()
- O Hippolyte (Sandhofe)
- O ignis spiritus ()
- O ineffabiliem virum (Sandhofe)
- O Jesu mi ()
- O Joachim (Vatican)
- O Joachim (Solesmes)
- Oleum effusum (Dominican)
- Oleum effusum (Solesmes 1961)
- Oleum effusum (Solesmes 1934)
- Oleum effusum nomen (Solesmes)
- Olim mundo minoratus (Solesmes)
- O lingua benedicta (Solesmes)
- O lumen (Dominican)
- O lumen Ecclesiae (Dominican)
- O lux beata Caelitum (Solesmes 2000s)
- O lux beata Caelitum (Dominican)
- O lux beata Caelitum (Solesmes)
- O lux beata Caelitum (Solesmes 1983)
- O lux beata Caelitum (Solesmes 1961)
- O lux beata Trinitas (Solesmes 2000s)
- O lux beata Trinitas (Dominican)
- O lux beata Trinitas (Cistercian)
- O lux beata Trinitas (aestivalis) (Solesmes 1934)
- O lux beata Trinitas (aestivalis) (Solesmes 1934)
- O lux beata Trinitas (hiemalis) (Solesmes 1934)
- O lux et decus (Dominican)
- O lux salutis nuntia (Solesmes 2019)
- O magnam dignitatem (Solesmes 1961)
- O magnum (Solesmes 1934)
- O magnum pietátis (Solesmes 1934)
- O Magnum Mysterium (English)
- O magnum mysterium (Solesmes 1961)
- O magnum mysterium (Sandhofe)
- O magnum mysterium (Resp.) (Gregofacsimil)
- O magnum pietatis (Solesmes)
- O magnum pietatis (Dominican)
- O magnum pietatis (Solesmes 1934)
- O magnum pietatis (Solesmes 1961)
- O Margarita poenitens (Solesmes)
- O Maria Dei cella (Solesmes)
- O Maria, gratia plena (Solesmes)
- O Maria mater pia (Solesmes)
- O Maria Mater pia Mater (Solesmes)
- O Maria rubens rosa (Engelberg)
- O Maria Virgo Honesta ()
- O Maria vitae via (Solesmes)
- O Maria vitae via (Solesmes)
- O Martine (Solesmes 1957)
- O Martine (Dominican)
- O martyr desiderio (Dominican)
- O martyr egregie (Dominican)
- O Martyr invictissime (Proprium Poloniae)
- O memoriale (Solesmes 2000s)
- O mi Jesu (Azeri)
- O mi Jesu (Annamitice)
- O mira caritas (Solesmes)
- O mira res (Solesmes 1957)
- Omne datum (Verona)
- Omne quod dat (Verona)
- Omne quod dat mihi (Solesmes 1934)
- Omne quod dat mihi (Solesmes 1961)
- Omne quod dat mihi Pater (Annamitice)
- Omnes amici mei (OSB)
- Omnes amici mei (Solesmes 1961)
- Omnes amici mei dereliquerunt (Sandhofe)
- Omnes Angeli (Solesmes 1934)
- Omnes Angeli eius (Solesmes 1981)
- Omnes angeli eius (Simplex)
- Omnes Angeli ejus (Solesmes 1934)
- Omnes Angeli ejus (Solesmes)
- Omnes angeli ejus (Dominican)
- Omnes autem (Verona)
- Omnes autem vos (Solesmes)
- Omnes autem vos (Solesmes 1961)
- Omnes autem vos fratres estis (Solesmes 1934)
- Omnes collaudant (Palmer & Burgess)
- Omnes collaudant (Verona)
- Omnes collaudant (Solesmes)
- Omnes collaudant (ad. lib.) (Solesmes)
- Omnes de Saba (Solesmes 1934)
- Omnes de Saba (Solesmes 1934)
- Omnes de Saba (Solesmes)
- Omnes de Saba (Solesmes 1934)
- Omnes de Saba (Vatican)
- Omnes de Saba (Solesmes)
- Omnes de Saba (Palmer & Burgess)
- Omnes de Saba (Solesmes)
- Omnes de Saba (Dominican)
- Omnes de Saba (Solesmes 1961)
- Omnes de Saba (Dominican)
- Omnes de Saba (Solesmes 1961)
- Omnes de Saba (Verona)
- Omnes de saba (English Adaptation)
- Omnes de Saba (Resp.) (Gregofacsimil)
- Omnes de Saba (Resp.) (Sandhofe)
- Omnes de Saba venient (Solesmes 1934)
- Omnes Gentes (Sandhofe)
- Omnes Gentes ()
- Omnes gentes (Palmer & Burgess)
- Omnes gentes (Palmer & Burgess)
- Omnes gentes (Palmer & Burgess)
- Omnes gentes (Verona)
- Omnes gentes (Comm.) (Vatican)
- Omnes gentes (Comm.) (Solesmes)
- Omnes gentes per gyrum (Solesmes 1961)
- Omnes gentes per gyrum (Solesmes 1934)
- Omnes gentes per gyrum (Dominican)
- Omnes gentes per gyrum (Solesmes)
- Omnes gentes plaudite (Palmer & Burgess)
- Omnes gentes plaudite (All) (Solesmes)
- Omnes gentes plaudite (All) (Vatican)
- Omnes gentes plaudite (Intr) (Vatican)
- Omnes gentes plaudite (Intr) (Solesmes)
- Omnes gentes plaudite (Intr) (Dominican)
- Omnes gentes, plaudite manubus (nova lat.) ()
- Omnes gentes (Ps.46 - Textus antiquus) (Solesmes)
- Omnes gentes quascumque (Solesmes 2000s)
- Omnes gentes quascumque (Solesmes 1981)
- Omnes gentes quascumque (Grad) (Vatican)
- Omnes gentes quascumque (Grad) (Solesmes)
- Omnes Gentes quascumque (Tonus IV) (Sandhofe)
- Omnes gentes quascumque (Tonus VI) (Sandhofe)
- Omnes inimici (Verona)
- Omnes inimici mei (Dominican)
- Omnes inimici mei (Solesmes)
- Omnes isti (Lyon)
- Omnes nationes (Solesmes)
- Omnes nationes (Solesmes 1934)
- Omnes nationes (Verona)
- Omnes populi (Dominican)
- Omnes populi (Proprium Poloniae)
- Omnes qui habebant (Verona)
- Omnes qui habebant (Solesmes 1961)
- Omnes qui habebant (Solesmes)
- Omnes qui habebant (Solesmes 1934)
- Omnes qui habebant (Dominican)
- Omnes Qui in Christo (English Adaptation)
- Omnes qui in Christo (Dominican)
- Omnes qui in Christo (Solesmes)
- Omnes qui in Christo (Vatican)
- Omnes Sancti (Solesmes 1934)
- Omnes Sancti (Annamitice)
- Omnes sancti (Solesmes 1961)
- Omnes Sancti quanta passi (Solesmes)
- Omnes sitientes (Solesmes)
- Omnes sitientes (Dominican)
- Omnes sitientes (Solesmes 1934)
- Omnes sitientes (Solesmes 2000s)
- Omnes sitientes (Solesmes 1961)
- Omnes sitientes (Vatican)
- Omnes sitientes (Verona)
- Omnes sunt administratorii (Solesmes 1961)
- Omnes sunt administratorii (Solesmes)
- Omnes sunt administratorii (Solesmes 1934)
- Omnes sunt administratorii (Dominican)
- Omnes una voce dixerunt (Sandhofe)
- Omnia detrimentum (Dominican)
- Omnia quaecumque voluit (Verona)
- Omnia quaecumque voluit (Solesmes 1981)
- Omnia quaecumque voluit (Solesmes 1934)
- Omnia quaecumque voluit (Solesmes 2000s)
- Omnia quae fecisti (Solesmes)
- Omnia quae fecisti (Palmer & Burgess)
- Omnia quae fecisti (Triplex)
- Omnia quae fecisti (Dominican)
- Omnia tempore (Sandhofe)
- Omnibus omnia (Solesmes)
- Omni die dic Mariæ (Solesmes)
- Omni die dic Mariae (Annamitice)
- Omnipotens (Dominican)
- Omnipotens adorande (Dominican)
- Omnipotens adorande (Sandhofe)
- Omnipotens adorande (Resp.) (Gregofacsimil)
- Omnipotens Sermo (Solesmes 2000s)
- Omnipotens Sermo (Verona)
- Omnipotens sermo (Solesmes 1961)
- Omnipotens sermo (Solesmes 1934)
- Omnipotenti (Dominican)
- Omnis arbor (Verona)
- Omnis autem (Verona)
- Omnis expertem (Solesmes 1957)
- Omnis expertem (Dominican)
- Omnis expertem (Annamitice)
- Omnis expertem (Solesmes 1961)
- Omnis expertem (Solesmes)
- Omnis expertem II (Annamitice)
- Omnis expertem maculae (Solesmes)
- Omnis gloria (Vatican)
- Omnis gloria (Solesmes)
- Omnis plebs (Dominican)
- Omnis pulchritudo (Dominican)
- Omnis pulchritudo Domini (Sandhofe)
- Omnis qui invocaverit (Dominican)
- Omnis qui invocaverit (Solesmes)
- Omnis qui invocaverit (Solesmes 1961)
- Omnis qui petit (Verona)
- Omnis qui petit (Dominican)
- Omnis qui se exaltat (Verona)
- Omnis qui se exaltat (Solesmes 2000s)
- Omnis sanctorum concio (Solesmes 1934)
- Omnis sanctorum concio (Solesmes 1934)
- Omnis sapientia (Verona)
- Omnis sapientia (Solesmes 1934)
- Omnis sapientia (Dominican)
- Omnis sapientia (Solesmes 1961)
- Omnis sapientia (Solesmes)
- Omnis spiritus (Verona)
- Omnis spiritus (Solesmes)
- Omnis spiritus (Solesmes 1961)
- Omnis spiritus (Dominican)
- Omnis spiritus (Solesmes 2000s)
- Omnis spiritus (Solesmes 1934)
- Omnis terra (Solesmes)
- Omnis terra (Triplex)
- Omnis terra (Dominican)
- Omnis terra (Palmer & Burgess)
- Omnis terra (Dominican)
- Omnis terra (Vatican)
- Omnis terra (Verona)
- Omnis terra (Solesmes 1961)
- Omnis terra adóret te (Simplex)
- Omnis terra adoret (Solesmes)
- Omnis terra adoret (Sandhofe)
- Omnis terra adoret te (Solesmes 1895)
- Omnis terra adoret (T. Paschali) (Solesmes)
- Omnis terra (Paschal Time) (Solesmes 1961)
- Omnis vallis (Solesmes 2000s)
- Omnis vallis (Dominican)
- Omnis vallis (Solesmes 2000s)
- Omnis vallis (Mode 5a) (Verona)
- Omnis vallis (Mode 2d) (Verona)
- Omni tempore (Gregofacsimil)
- Omni tempore (Dominican)
- Omni tempore (Solesmes 2007)
- O mors (Dominican)
- O mors (Solesmes)
- O mors (Solesmes 1934)
- O mors (Verona)
- O mulier (Solesmes 1961)
- O mulier (Dominican)
- O mulier magna est (Solesmes 1934)
- O mulier magna est (Solesmes)
- O mundi Domina (Solesmes 1957)
- O mundi lampas (Dominican)
- O nata lux de lumine (Solesmes)
- O nata lux de lumine (Cistercian)
- O nimis felix (Solesmes 1934)
- O nimis felix (Solesmes 1957)
- O nimis felix (Solesmes 1961)
- O nimis felix (Solesmes 1983)
- O nimis felix (Dominican)
- O nimis felix meritique (Solesmes)
- O nimis felix meritique (Alter tonus) (Solesmes)
- O nobilissima viriditas (J. Schmidt-Gorg 1969 ed.)
- O novi mundi lampas (Dominican)
- O Oliva fructifera (Cistercian)
- O Oriens (Dominican)
- O Oriens (Solesmes)
- O Oriens (Verona)
- O Oriens (Solesmes 1961)
- O Oriens (Solesmes 2000s)
- O Oriens splendor (Solesmes)
- O Oriens splendor lucis (Solesmes 1934)
- O Panis dulcissime (Solesmes)
- O panis dulcissime (Solesmes 1957)
- O pastor aeterne (Dominican)
- O pastor animarum ()
- O pastor animarum ()
- Opera manuum eius (Verona)
- Opera manuum tuarum (Solesmes 1934)
- Opera manuum tuarum (Annamitice)
- Opera manuum tuarum (Solesmes 1961)
- Opera manuum tuarum (Dominican)
- Operamini (Verona)
- Opera quae ego (Verona)
- O per omnia (Dominican)
- Operuit caelos (Verona)
- Opes decusque regium (Solesmes)
- O Petre (Dominican)
- O Petre lumen errantium (Proprium Ordinis de Mercede)
- O pie Deus (Offertoriale 1935)
- Oportebat (Palmer & Burgess)
- Oportebat pati (Solesmes)
- Oportebat pati (Dominican)
- Oportebat pati (Verona)
- Oportebat pati Christum (Solesmes 1934)
- Oportebat pati Christum (Solesmes)
- Oportebat pati Christum (Vatican)
- Oportebat pati Christum (Solesmes 2000s)
- Oportet te fili (Solesmes)
- Oportet te fili (Dominican)
- Oportet te fili (Vatican)
- Opportet illum (Sandhofe)
- Oppressit me dolor (Solesmes)
- Oppressit me dolor (Dominican)
- Oppressit me dolor (Solesmes 1961)
- Oppresssit me dolor (Solesmes 1934)
- Opprobrium factus sum nimis inimicis (Sandhofe)
- O praeclarum mundi jubar (Solesmes)
- O praedicator gratiae! (Solesmes)
- O Prima Virgo (Solesmes)
- O prima Virgo prodita (Solesmes 1934)
- O prima Virgo prodita (Solesmes 1961)
- Optatus votis (Cistercian)
- Optatus votis omnium (Solesmes 1957)
- Optatus votis omnium (Solesmes 1983)
- Optimam partem (Palmer & Burgess)
- Optimam partem (Solesmes)
- Optimam partem (Palmer & Burgess)
- Optimam partem (Verona)
- Optimam partem (Vatican)
- Optimam partem... Bronislava (Proprium Poloniae)
- Optime Pater (Dominican)
- O pulchrae facies (J. Schmidt-Gorg 1969 ed.)
- O quam (Solesmes 1934)
- O quam gloriósum est regnum (Solesmes 2000s)
- O quam beata urbs (Venetian)
- O quam bonus (Solesmes)
- O quam bonus (Vatican)
- O quam felix (Dominican)
- O quam glorifica (Solesmes 1957)
- O quam glorifica (Cistercian)
- O quam glorifica (Solesmes 1983)
- O quam gloriosum est (Solesmes)
- O quam gloriosum est regnum (Solesmes 1934)
- O quam gloriosum est regnum (Dominican)
- O quam gloriosum est regnum (Solesmes 1961)
- O quam gloriosus est beatus (Dominican)
- O quam metuendus (Solesmes 1961)
- O quam metuendus (Dominican)
- O quam metuendus (Solesmes 1934)
- O quam metuendus est (Sandhofe)
- O quam mirabilis ()
- O quam praeclara sunt merita (Solesmes 1934)
- O quam pulchra (Solesmes)
- O quam pulchra (Vatican)
- O quam pulchra est (Sandhofe)
- O quam pulchra... immortalis (Solesmes)
- O quam speciosa (Dominican)
- O quam speciosi (Solesmes 1961)
- O quam speciosi pedes (Solesmes)
- O quam suavis (Solesmes 1961)
- O quam suavis (Verona)
- O quam suavis (Dominican)
- O quam suavis est (Solesmes 2000s)
- O quam suavis est (Solesmes 1934)
- O quam suavis est (Solesmes)
- O quantum in Cruce (Solesmes 1957)
- O quantus (Dominican)
- O quot undis lacrimarum (Solesmes 1957)
- O quot undis lacrimarum (Sandhofe)
- O radio ()
- O Radix (Dominican)
- O Radix Iesse (Verona)
- O Radix Iesse (Solesmes 2000s)
- O radix Jesse (Solesmes)
- O radix Jesse (Solesmes 1934)
- O radix Jesse (Solesmes 1961)
- O radix Jesse (Solesmes)
- O radix Jesse (Dominican)
- Orante sancta Lucia (Dominican)
- Orante sancta Lucia (Solesmes)
- Orante sancta Lucia (Solesmes 1961)
- Orante sancta Lucia (Solesmes 1934)
- Orante sancto Clememte (Dominican)
- Orante sancto Clemente (Solesmes)
- Orante sancto Clemente (Dominican)
- Orante sancto Clemente (Solesmes 1961)
- Orante sancto Clemente (Sandhofe)
- Orante sancto Clemente (Solesmes 1934)
- Orantibus in loco isto (Sandhofe)
- Ora pro nobis (Dominican)
- Ora pro nobis... allel. (Dominican)
- Ora pro nobis sancte Joseph (Solesmes 1961)
- Orate pro persequentibus (Verona)
- Orate pro persequentibus (Solesmes 2000s)
- Orate pro persequentibus (Verona)
- Orate pro persequentibus (Solesmes 2000s)
- Oratio Jeremiæ Prophetæ (Dominican)
- Oratio felix (Annamitice)
- Oratio felix ()
- Oratio mea (Solesmes)
- Oratio mea (Dominican)
- Oratio mea (Vatican)
- Oratione et devotione (Dominican)
- Oravi Deum (Dominican)
- Oravi Deum (Solesmes)
- Oravi Deum (Palmer & Burgess)
- Oravi Deum (verses) (Offertoriale 1935)
- Oravit Jacob et dixit (Resp.) (Gregofacsimil)
- Oravit sanctus Andreas (Sandhofe)
- Orbe qui Praesul (Solesmes)
- Orbis Factor (Sarum)
- Orbis factor (Stingl)
- Orbis Patrator optime (Solesmes 1934)
- Orbis patrator optime (Dominican)
- Ordines angelorum ()
- O Redemptor (Solesmes 1961)
- O Redemptor (Simplex)
- O Redemptor (Annamitice)
- O Redemptoris pietas (Solesmes)
- O Regem caeli (Sandhofe)
- O Regem caeli ()
- O Regem caeli (Resp.) (Gregofacsimil)
- Oremus, dilectissimi nobis ()
- Oremus omnes (Solesmes 1961)
- Oremus omnes (Solesmes 1934)
- Oremus omnes (Dominican)
- Oremus omnes ad Dominum (Solesmes)
- Oremus pro Antistite (Solesmes 1957)
- Oremus pro Pontifice (Chmerice)
- Oremus pro Pontifice (Solesmes)
- Oremus pro Pontifice (Annamitice)
- Oremus pro Pontifice (cantus II) (Solesmes)
- O res admirabilis (Solesmes)
- O rex aeterne Domine (Solesmes)
- O Rex gentium (Solesmes 1934)
- O Rex gentium (Verona)
- O Rex gentium (Solesmes)
- O Rex gentium (Dominican)
- O Rex gentium (Solesmes)
- O Rex gentium (Solesmes 2000s)
- O Rex gentium (Solesmes 1961)
- O Rex gloriae (Verona)
- O Rex gloriae (Solesmes 1961)
- O Rex gloriae (Solesmes 1934)
- O Rex gloriae (Dominican)
- O Rex gloriae Domine (Solesmes)
- O Rex gloriose (Dominican)
- O rex optime (Antiphonale Solesmense 1935)
- Oriens ex alto (Verona)
- Orietur diebus (Verona)
- Orietur diebus (Sandhofe)
- Orietur in diebus (Solesmes 1961)
- Orietur in diebus (Nocturnale Vaticanum)
- Orietur sicut sol (Solesmes)
- Orietur sicut sol (Dominican)
- Orietur sicut sol (Verona)
- Orietur sicut sol (Solesmes 2000s)
- Orietur stella Jacob (Sandhofe)
- Orietur stella (Resp.) (Gregofacsimil)
- Originale crimen (Exaltatio) (Dominican)
- Originale crimen (Inventio) (Dominican)
- Oriétur sicut sol (Solesmes 1934)
- Ornatam in monilibus (Sandhofe)
- Ornatam in monilibus (Resp.) (Gregofacsimil)
- Ornaverunt (Sandhofe)
- Ornaverunt faciem templi (Gregofacsimil)
- Ornavit me (Ambrosian)
- O robur Domini (Dominican)
- O Roma felix (Solesmes 1934)
- O Rosa (Dominican)
- Ortus refulget lucifer (Solesmes)
- O rubor sanguinis ()
- Orémus pro Antístite (alt) ()
- O sacrosancta Trinitas (Solesmes 1983)
- O sacrum convivium (Solesmes 1961)
- O sacrum convivium (Solesmes 1957)
- O sacrum convivium (Verona)
- O sacrum convivium (Solesmes 2000s)
- O sacrum convivium (Dominican)
- O sacrum convivium (Solesmes)
- O Salutaris Hostia (abbé du Gué)
- O Salutaris Hostia (Annamitice)
- O salutaris Hostia (Polish)
- O salutaris Hostia (Polish)
- O salutaris Hostia (Amiens)
- O Salutaris Hostia I (Annamitice)
- O salutaris Hostia I (Solesmes)
- O salutaris Hostia I (Solesmes)
- O salutaris Hostia II (Annamitice)
- O salutaris Hostia II (Solesmes)
- O salutaris Hostia II (Solesmes)
- O Salutaris Hostia II (cantus ad processiones) (Solesmes)
- O salutaris Hostia III (Solesmes)
- O salutaris Hostia III (Solesmes)
- O Salutaris Hostia III (cantus ad processiones) (Solesmes)
- O salutaris Hostia IV (Solesmes)
- O Salutaris Hostia IV (cantus ad processiones) (Solesmes)
- O salutaris Hostia V (Solesmes)
- O salutaris Hostia VI (Solesmes)
- O Salutaris Hostia VI (cantus ad processiones) (Solesmes)
- O salutaris Hostia VII (Solesmes)
- O Salutaris Hostia VII (cantus ad processiones) (Annamitice)
- O Salutaris Hostia VII (cantus ad processiones) (Solesmes)
- O Salutaris Hostia Sacra (Annamitice)
- O Salutaris Hostia Sacra ()
- O Salutaris Hostia (Vexilla Regis) (Solesmes)
- O sancta mundi domina (Solesmes)
- O sanctissima (Annamitice)
- O sanctissima (Siciliae)
- O Sapientia (Solesmes)
- O Sapientia (Solesmes 1961)
- O Sapientia ()
- O Sapientia (Solesmes 2000s)
- O Sapientia (Solesmes 1934)
- O Sapientia ()
- O Sapientia (Solesmes)
- O Sapientia (Solesmes 1961)
- O Sapientia (Dominican)
- O Sapientia (Verona)
- O sator rerum (Solesmes)
- O sempiternae curiae (Solesmes)
- O Sidus Hispaniae ()
- O sidus refulgens (Solesmes)
- Os justi (Vatican)
- Os justi (Solesmes 1961)
- Os justi (Dominican)
- Os justi (Palmer & Burgess)
- Os justi (Solesmes)
- Os justi (Palmer & Burgess)
- Os justi (Solesmes 1934)
- Os justi (solesmes 1934)
- Os justi (Dominican)
- Os justi (Vatican)
- Os justi (Grad.) (Solesmes)
- Os justi (Paschal Time) (Solesmes 1961)
- Os justi (T.P.) (Solesmes 1934)
- Os meum loquetur (Nocturnale Vaticanum)
- Os meum loquetur (Sandhofe)
- O sola (Solesmes 1934)
- O sola magnarum (Solesmes 1961)
- O sola magnarum (Solesmes)
- O sola magnarum urbium (Cistercian)
- O sol salutis intimis (Solesmes)
- O sol salutis intimis (Alter tonus) (Solesmes)
- O Sophia (Solesmes)
- O Sophia (Solesmes)
- O spem miram (Dominican)
- O spem miram (Dominican)
- O spem miram ()
- O splendor pudicitiae (Solesmes)
- O sponsa Christi (Dominican)
- Os suum aperuit sapientiae (Sandhofe)
- Ostende (Dominican)
- Ostende (Palmer & Burgess)
- Ostende mihi (Vatican)
- Ostende mihi (Dominican)
- Ostende mihi (Solesmes)
- Ostende nobis (Solesmes 1961)
- Ostende nobis (Dominican)
- Ostende nobis (Vatican)
- Ostende nobis (Vatican)
- Ostende nobis (Dominican)
- Ostende nobis (Solesmes)
- Ostende nobis (Salmodia)
- Ostende nobis (Solesmes)
- Ostende nobis (Solesmes)
- Ostende nobis (Annamitice Novus Ordo)
- Ostende nobis (Dominican)
- Ostende nobis Domine (Solesmes)
- Ostende nobis Domine (Vatican)
- Ostende nobis Domine (Solesmes 2000s)
- Ostende nobis Domine (Solesmes 1934)
- Ostende nobis Domine (Solesmes 1934)
- Ostende nobis Domine (Verona)
- Ostendit (Dominican)
- Ostendit mihi angelus (Sandhofe)
- Ostendit mihi Dominus (Solesmes)
- O stupor (Dominican)
- O superni sponsa (Dominican)
- O Thoma (Dominican)
- O Thoma Didyme (Dominican)
- O Trinitas laudabilis (Dominican)
- O tu spes mea Maria (Solesmes)
- O vera (Solesmes 2000s)
- O vera summa (Verona)
- Oves meæ (Solesmes 1934)
- Oves meae (Dominican)
- Oves meae (Verona)
- Oves meae (Cistercian)
- Oves meae (Solesmes 1961)
- Oves meae (Solesmes)
- Oves meae vocem (Solesmes)
- Oves pascuae (Dominican)
- O vir beate (Solesmes 1983)
- O virga ac diadema ()
- O Virgo Maria (Solesmes 1957)
- O virgo mater (Solesmes 1983)
- O virgo maxima (Dominican)
- O virgo o doctor (Dominican)
- O Virgo pulcherrima (Solesmes)
- O Virgo virginum (Dominican)
- O Virgo virginum (Solesmes 1957)
- O virtus sapientiae ()
- O virum ineffabilem (Solesmes)
- O virum ineffabilem (Solesmes 1961)
- O virum ineffabilem (Dominican)
- O virum ineffabilem (Solesmes 1934)
- O virum mirabilem (Dominican)
- O vos aetherei (Solesmes)
- O vos omnes (Dominican)
- O vos omnes (Solesmes)
- O vos omnes (Dominican)
- O vos omnes (Solesmes 1961)
- O vos omnes (Solesmes)
- O vos omnes (Dominican)
- O vos omnes (Vatican)
- O vos omnes (Solesmes)
- O vos omnes (Solesmes 1934)
- O vos omnes (Sandhofe)
- O vos omnes (Solesmes)
- O vos omnes (Vatican)
- O vos omnes (Verona)
- O vos omnes (OSB)
- O vos omnes (Solesmes 1961)
- O vos unanimes (Solesmes 1934)