46 R.P. Winnington-Ingram, Mode in Ancient Greek Music, (Camridge University Press, 1936), pp. 66-71. See also: Andrew Barker, Scientific Method in Ptolemy’s Harmonics, (Cambridge University Press, 2000), pp. 167, 169-175.; André Barbera, ‘Metabolē’, in Grove Music Online, Oxford Music Online, <http://www.oxfordmusiconline.com/subscriber/article/grove/music/18507> [accessed 11 July 2012].