Agni Purana 64.15

64.15

āpo devīti girijair ekāśīvighaṭaistataḥ /
snāpayedvaruṇasyeti tvanno varuṇā cārghyakaṃ //

with ‘āpo devīḥ’ with mountain water, then with eighty-one jars
he should bathe him with ‘varuṇasya’ and offer the water offering with ‘tvanno varuṇa’;