According to LEVERETT 1990, 207-209, and LEVERETT 1994, 160, this mass should be the "Alia missa brevis eiusdem toni" cited in the index of Librone 2 and whose folio number is missing. Bonnie J. Blackburn (s.v. "Gaffurius [Gafurius], Franchinus", in "Grove Music Online") agrees with this hypothesis. On the contrary, according to Amerigo Bortone (AMMM 3, v-vi), the Mass on f. 110v is the "Missa brevis et expedita" and the "Alia missa" is the following one (f. 114v). See also the further notes regarding [II.23].