People - Ancient Greece: Cleonides It is an ancient Greek musical treatise attributed
Cleonides in Wikipedia
CLEONIDES The Greek musical treatise attributed to Euclid, is in some MSS. attributed to Cleonides. [Eucleides] His age and history are wholly unknown
According to Thomas J. Mathiesen the clearest account of the technical aspects of Aristoxenos musical theory are to be found in a manuscript Harmonica Introductio often attributed to Cleonides.