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 the Argives invaded Phliasia; but being ambushed by the Phliasians and the Argive exiles they lost about eighty men. Also the Athenians at Pylos took much booty from the Lacedaemonians;
but even this did not move the Lacedaemonians to renounce the treaty and make war upon them. They made proclamation, however, that any one of their own people who wished might make reprisals upon the Athenians.
The Corinthians also went to war with the Athenians on account of some private differences; but the rest of the Peloponnesians kept quiet.