History of the Peloponnesian War
Thucydides
Thucydides. History of the Peloponnesian War. Crawley, Richard, translator. London and Toronto: J. M. Dent and Sons Ltd.; New York: E. P. Dutton and Co., 1914.
About the same time three Lacedaemonians—Ramphias, Autocharidas, and Epicydidas—led a reinforcement of nine hundred heavy infantry to the towns in the direction of Thrace, and arriving at Heraclea in Trachis reformed matters there as seemed good to them.
While they delayed there, this battle took place and so the summer ended.