History - Resurrexi
Apr 25, 2023 (Christopher Jaser)
added Einsiedeln and Laon MSS links
remarks
Melodic restoration taken from Dom Gajard's "Le plus belles melodies gregoriennes"
Einsiedeln 121, page 205: https://www.e-codices.unifr.ch/de/sbe/0121/206/0/
Laon 239, page 103: https://imslp.org/wiki/Gradual,_F-LA_Ms_239_(Gregorian_Chant)