Passage 4.15.8
Λακεδαιμονίοις δὲ ἦλθον Κορίνθιοι συμμαχήσοντες καὶ Λεπρεατῶν τινες κατὰ ἔχθος τὸ Ἠλείων· Ἀσιναίοις δὲ ὅρκοι πρὸς ἀμφοτέρους ἦσαν. τὸ δὲ χωρίον τοῦτο, Κάπρου σῆμα, ἔστι μὲν ἐν Στενυκλήρῳ τῆς Μεσσηνίας, Ἡρακλέα δὲ αὐτόθι ὅρκον ἐπὶ τομίων κάπρου τοῖς Νηλέως παισὶ δοῦναι καὶ λαβεῖν παρὰ ἐκείνων λέγουσιν.
The Corinthians came to help the Spartans, as did certain Lepreans, because of their hostility toward the Eleans; the Asinaeans, however, had sworn oaths to both sides. This particular place, called "Tomb of the Boar," is situated in Stenykleros in Messenia; they say that here Heracles gave and received an oath with the sons of Neleus upon pieces of a sacrificed boar.