Dates from Grove (says Caron fl. 146075)
Wegman: Source: VatSP B80, fols. 166v-181r.
Carons authorship proposed by Christopher A. Reynolds, Papal Patronage and the Music of St. Peters, 1380-1513 (Berkeley, Los Angeles, London: University of California Press, 1995), 203-227. The style of Missa Thomas cesus is very closely related to that of the anonymous Lhomme armé Masses in NapBN 40, so much so that either they must be by the same man, or else were written by composers working in immediate proximity. Thomas cesus must date from the 1450s; one can hear the influence of the anonymous English Missa Caput at every turn.
Unclear what type of mass this is. No model in Wegman.