Passage 8.5.6
Κυψέλου δὲ τοῦ Αἰπύτου βασιλεύοντος μετὰ Αἴπυτον, ὁ Δωριέων στόλος οὐ διὰ τοῦ Κορινθίων ἰσθμοῦ, καθὰ ἐπὶ τρεῖς τὰς πρότερον γενεάς, ναυσὶ δὲ κατὰ τὸ ὀνομαζόμενον Ῥίον κάτεισιν ἐς Πελοπόννησον· πυνθανόμενός τε τὰ ἐς αὐτοὺς ὁ Κύψελος, ὃν τῶν Ἀριστομάχου παίδων οὐκ ἔχοντά πω γυναῖκα εὕρισκε, τούτῳ τὴν θυγατέρα ἐκδοὺς καὶ οἰκειωσάμενος τὸν Κρεσφόντην αὐτός τε καὶ οἱ Ἀρκάδες ἐκτὸς ἑστήκεσαν δείματος.
When Cypselus, the son of Aepytus, succeeded Aepytus as king, the Dorian army entered the Peloponnese—not by way of the Isthmus of Corinth, as had happened three generations earlier—but sailed along the place called Rhium. Cypselus, upon learning about their intentions, discovered that Cresphontes, one of the sons of Aristomachus, did not yet have a wife; thus he gave him his daughter in marriage, and having formed this alliance with Cresphontes, both he himself and the Arcadians remained free from fear.