Skandapurana 5.246.11

5.246.11

aikyaṃ viṣṇugaṇaiḥ kurvandadhre rūpaṃ mahādbhutam ..
tadā hariharākhyaṃ ca dehārddhābhyāṃ dadhāra saḥ..6.247.10..
haraścaivārddhadehena viṣṇurarddhena cābhavat ..
ekato viṣṇucihnāni haracihnāni caikataḥ..11..

effecting unity with the hosts of Viṣṇu, assumed a most wondrous form. / He then bore the name Hari-Hara by means of the two halves of his body: / / Hara was one half of the body, and Viṣṇu was the other half. / On one side were the marks of Viṣṇu, and on the other side were the marks of Hara.