Devibhagavatapurana 1.5.10

1.5.10

gatāḥ sarve'tha vaikuṇṭhaṃ draṣṭuṃ devaṃ janārdanam |
devakāryārthasiddhyarthaṃ makhānāmadhipaṃ prabhum ||

Then they, for the sake of success in Deva's well, went to the region of Vaikuntha to meet with the Deva Janârdana, the Lord of sacrifices. There the Devas, not finding Visnu, came to know by their Dhyân (meditation) where Bhagavân Visnu was staying and thither they went. They saw that the Lord Visnu, the Deva of the Devas was lying unconscious, being under the arms of Yoganidrâ (the yogic sleep). Therefore they took their seats there. Seeing the Lord of the universe asleep, Brahmâ, Rudra and the other Devas became anxious.