Flavius Josephus, The Wars of the Jews
William Whiston, A.M., Ed.

[230] Petus then sent some of his men to seize upon Samosate, and by their means took possession of that city, while he went himself to attack Antiochus with the rest of his army. However, the king was not prevailed upon by the distress he was in to do any thing in the way of war against the Romans, but bemoaned his own hard fate, and endured with patience what he was not able to prevent. But his sons, who were young, and unexperienced in war, but of strong bodies, were not easily induced to bear this calamity without fighting. Epiphanes, therefore, and Callinicus, betook themselves to military force; and as the battle was a sore one, and lasted all the day long, they showed their own valor in a remarkable manner, and nothing but the approach of night put a period thereto, and that without any diminution of their forces; yet would not Antiochus, upon this conclusion of the fight, continue there by any means, but took his wife and his daughters, and fled away with them to Cilicia, and by so doing quite discouraged the minds of his own soldiers. Accordingly, they revolted, and went over to the Romans, out of the despair they were in of his keeping the kingdom; and his case was looked upon by all as quite desperate. It was therefore necessary that Epiphanes and his soldiers should get clear of their enemies before they became entirely destitute of any confederates; nor were there any more than ten horsemen with him, who passed with him over Euphrates, whence they went undisturbed to Vologeses, the king of Parthie, where they were not disregarded as fugitives, but had the same respect paid them as if they had retained their ancient prosperity.