The Agniṣvāttas, the Barhiṣadas, the Saumyas and the Ājyapas are the Pitās. They are either sāgnika or niragnika. The wife of all these Pitās is Svadhā, who is the daughter of King Dakṣa.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
अग्निष्वात्ता बर्हिषदः सौम्याः पितर आज्यपाः । साग्नयोऽनग्नयस्तेषां पत्नी दाक्षायणी स्वधा
agniṣvāttā barhiṣadaḥ saumyāḥ pitara ājyapāḥ | sāgnayo'nagnayasteṣāṃ patnī dākṣāyaṇī svadhā
SB 4.1.63