I am preparing an edition of Viadana's Missa Prima Dominicalis for solo Tenor. The Gloria and Credo are alternatim settings which use Missa 'Orbis factor'. The second invocation of the Agnus Dei is also chant. I have made an edition of three movements with a Solesmes-style transcription of the chant, but I also want to investigate the possibility of an edition with chant verses notated according to the principles in Giovanni Guidetti's Directorium chori (1582). I have this publication, but only the Gloria intonations for some masses are given. I wonder if someone has made a complete edition of Missa 'Orbis factor' according to Guidetti's principles?