History of the Peloponnesian War

Thucydides

Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.

About the same time, as the summer was ending, the Ambraciots themselves, with many of the barbarians whom they had summoned to their standard, made an expedition against the Amphilochian Argos and the rest of Amphilochia.

And enmity between them and the Argives first began from the following circumstance.