The main source of Archytas, fr. 1 Diels-Kranz is Porphyr. in Ptol. harmon. p. 56,5–57,27 Düring; there is also an extensive quotation of its initial part in Nicomachus, Introd. Arithm. p. 6,16–7,5 Hoche. In recent years both the text and the interpretation of this fragment, whose authenticity was questioned by W. Burkert, have been re-examined, and a good deal of progress has been made especially by paying more attention to the nature of Nicomachus' quotation and its context.