Shiva Purana
आयतिर्नियतिश्चैव पत्न्यौ द्वे भृगुपुत्रयोः ॥ स्वायंभुवे ऽंतरे पूर्वं कथितस्ते तदन्वयः ॥ ५४ ॥
Āyati and Niyati became the wives of the sons of Bhṛgu. I have mentioned to you about their race in Svāyambhuva Manvantara.
english translation
Ayatirniyatizcaiva patnyau dve bhRguputrayoH ॥ svAyaMbhuve 'Mtare pUrvaM kathitaste tadanvayaH ॥ 54 ॥
hk transliteration by Sanscript