Offertoriale is an exceedingly rare book, appeared in 1935 to provide the complete offertory verses for the Offertory chant in the Roman Rite of Mass. These are not psalm tone settings, but thoroughly composed chants that add a beautiful dimension to the chant at this point in Mass.
“After the Offertory Antiphon the choir may sing to the ancient Gregorian chants those Verses which it was once customary to sing at this place.” — 1958 Instruction De musica sacra et sacra liturgia by Pope Pius XII.
Offertoriale Index of Gregorian Chants
