The Mass [IV.12] was identified by STAEHELIN 1973, 82, with the "La basse danza" ascribed to Gaffurius in BERWIN-HIRSCHFELD 1892, 91. A "Messa, La Bassadanza" is ascribed to Gaffurius also in ANNALI 1885. According to WARD 1986, this Mass constitutes a cycle with the two previous motets ([IV.10] and [IV.11]); therefore she extends the attribution to "Assumpta es Maria" and "Vidi speciosam".