Passage 5.26.4
τοῖς δὲ ἐργασαμένοις αὐτά, γένος οὖσιν Ἀργείοις, Διονυσίῳ τε καὶ Γλαύκῳ, διδάσκαλόν σφισιν οὐδένα ἐπιλέγουσιν· ἡλικίαν δὲ αὐτῶν ὁ τὰ ἔργα ἐς Ὀλυμπίαν ἀναθεὶς ἐπιδείκνυσιν ὁ Μίκυθος. τὸν γὰρ δὴ Μίκυθον τοῦτον Ἡρόδοτος ἔφη ἐν τοῖς λόγοις, ὡς Ἀναξίλα τοῦ ἐν Ῥηγίῳ τυραννήσαντος γενόμενος δοῦλος καὶ ταμίας τῶν Ἀναξίλα χρημάτων ὕστερον τούτων ἀπιὼν οἴχοιτο ἐς Τεγέαν τελευτήσαντος Ἀναξίλα.
As to those who created these works—two Argives by birth, Dionysius and Glaucus—they mention no teacher at all. Mikythos, who dedicated the artists' works at Olympia, indicates their approximate period. About this very Mikythos, Herodotus mentions in his account that he was a slave of Anaxilas, the tyrant of Rhegium, and steward of the wealth of Anaxilas. Later, after Anaxilas' death, Mikythos departed from there and went to Tegea.