Kapilapurana 3.29

3.29

tataḥ suptotthito rājā na dṛṣṭvā śyāmasundaram
ruroda bhṛśaduḥkhārtaḥ kṛṣṇa kṛṣṇeti kīrtayan

Then, rising from sleep, not seeing the dark and handsome one, / the king wept, afflicted by intense sorrow, crying: “O Kṛṣṇa, Kṛṣṇa!”