Passage 4.15.2
ἐν δὲ Λακεδαίμονι οἵ τινες τηνικαῦτα ἔτυχον βασιλεύοντες, Τυρταῖος μὲν τὰ ὀνόματα οὐκ ἔγραψε, Ῥιανὸς δʼ ἐποίησεν ἐν τοῖς ἔπεσι Λεωτυχίδην βασιλέα ἐπὶ τοῦδε εἶναι τοῦ πολέμου. Ῥιανῷ μὲν οὖν ἔγωγε οὐδαμῶς κατά γε τοῦτο συνθήσομαι· Τυρταῖον δὲ καὶ οὐ λέγοντα ὅμως εἰρηκέναι τις ἂν ἐν τῷδε ἡγοῖτο. ἐλεγεῖα γὰρ ἐς τὸν πρότερόν ἐστιν αὐτῷ πόλεμον· ἀμφʼ αὐτῇ δʼ ἐμάχοντʼ ἐννέα καὶ δέκʼ ἔτη νωλεμέως, αἰεὶ ταλασίφρονα θυμὸν ἔχοντες, αἰχμηταὶ πατέρων ἡμετέρων πατέρες. Tyrtaeus, unknown location.
Now, in Lacedaemon, who precisely were kings at that time Tyrtaeus has not recorded; but Rhianus writes in his poetry that Leotychides was king during this war. In this particular I certainly will not agree with Rhianus at all; but although Tyrtaeus himself does not name a ruler explicitly, one might yet conclude that he has spoken indirectly about it. His elegies, indeed, refer to an earlier war, saying: "For nineteen years continuously fought they around it, Ever unyielding in courage, our fathers, warriors with spear, fathers of our fathers."