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.
The Lacedaemonians were now assailed on both sides, and—to compare a small affair with a great one—were in the same evil case as they had been at Thermopylae; for there they had perished when the Persians got in their rear by the path,[*](cf. Hdt. vii. 213.) and here they were caught in the same way. Since, then, they were now assailed on both sides they no longer held out, but, fighting few against many and withal weak in body from lack of food, they began to give way. And the Athenians by this time were in possession of the approaches.
But Cleon and Demosthenes, realizing that if the enemy should give back ever so little more they would be destroyed by the Athenian army, put a stop to the battle and held back their own men, wishing to deliver them alive to the Athenians and in hopes that possibly, when they heard the herald's proclamation, they would be broken in spirit and submit to the present danger.
Accordingly, they caused the herald to proclaim that they might, if they wished, surrender themselves and their arms to the Athenians, these to decide their fate as should seem good to them.