This “soneto” is part of a fantasia by Francesco da Milano, first published in 1536 (Ness nº 15). Arthur Ness comments (private communication to John Griffiths, 18 Sep 1994) “This and Francesco’s Fantasia Nº 13 (Valderrabano Soneto fol 92v [va155]—both identified by John Robinson—seem to be distillations of the Francesco ricercars as they come down in Italian sources, perhaps several removes from Francesco.” The comparison shows that Valderrábano has used the first half of Franseco’s piece: The relationship is close: Francesco #15 (total bars: 63 = 125 semibreves) // Valderrábano soneto (56 semibreves) The two borrowed passages are:
1. Francesco 1-12 = Valderrábano 4-25
2. Francesco 16-26 = Valderrábano 27-45
Pujol edits this piece as Soneto XVII (pujol1965).