The Brief Treatise on Ratios That Pertain to Music (1409) is a
concise summary of the
traditional doctrine of ratios. In
A Little Treatise on the Method of Dividing the Monochord (1413) Prosdocimo established, for the first time in Italy, a complete Pythagorean monochord, dividing the octave into seven natural notes, five flats, and five sharps not enharmonically equivalent to the flats.
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