Bhagavatapurana 4.1.4

4.1.4

yas tayoḥ puruṣaḥ sākṣād viṣṇur yajña-svarūpa-dhṛk /
yā strī sā dakṣiṇā bhūter aṃśa-bhūtānapāyinī //

4. Of the two, the male child was none other than Vishnu who had assumed the form of Yajna; the female was called Dakshinā and was a portion of Lakshmi, inseparable (from her Lord Vishnu).