Titus Livius (Livy), The History of Rome, Book 33
Evan T. Sage, Ph.D. Professor of Latin and Head of the Department of Classics in the University of Pittsburgh, Ed.

14. At the same time, and, as some have related, on the very same day, the Achaeans routed the king's general Androsthenes in a pitched battle near Corinth. [2] Philip intended to hold this city as a stronghold against the Greek cities, and when he had invited there the leading citizens under pretence of discussing with them the number of cavalry the Corinthians could furnish for [3] the war, he had held them as hostages, and in addition to five hundred Macedonians and eight hundred auxiliaries of various nations, the [4] number that had already been there for some time, he had sent there a thousand Macedonians and twelve hundred Thracians and Illyrians and eight hundred Cretans, for this people fought on both sides. [5] Added to these were one thousand Boeotians, Thessalians and Acarnanians, all provided with shields, and seven hundred of the youth of the Corinthians themselves, filling up his numbers to six thousand armed men, and these gave Androsthenes confidence enough to risk a decisive battle. [6] Nicostratus, the praetor of the Achaeans, was at Sicyon with two thousand infantry and one hundred cavalry, but, seeing himself inferior both in numbers and in the quality of his troops, he would not leave his fortifications. [7] The king's infantry and cavalry were roaming about and ravaging the lands of Pellene, Phlius and Cleonae, and finally crossed into the territory of Sicyon, taunting the enemy with cowardice; [8] likewise they skirted with their ships the whole coast of Achaea and laid it waste. [9] When the enemy was thus engaged in scattered groups and, as often happens in [p. 315]cases of over-confidence, with a lack of vigilance, -¹ Nicostratus, in the hope of attacking them unexpectedly, sent secret messages to the neighbouring states, naming the day and [10] fixing the numbers from each state to assemble at Apelaurum —this place is in the land of Stymphalia. [11] When all was ready on the appointed day, he at once set out by night through the country of the Phliasii and arrived at Cleonae, no one knowing what he was planning. [12] He had with him five thousand infantry, including ... light-armed troops, and three hundred cavalry. With these forces, after first sending out scouts to find out in which direction the enemy was moving, he waited.