Shiva Purana
गोत्राणि नामभिस्तेषां वासिष्ठानां महात्मनाम् ॥ स्वायंभुवे ऽंतरे ऽतीतान्यर्बुदानि शतानि च ॥ ३५ ॥
Their descendants with the names of Vasiṣṭha were in hundreds and hundred millions all in Svāyambhuva Manvantara.
english translation
gotrANi nAmabhisteSAM vAsiSThAnAM mahAtmanAm ॥ svAyaMbhuve 'Mtare 'tItAnyarbudAni zatAni ca ॥ 35 ॥
hk transliteration by Sanscript