SB 8.1.27

चतुर्थ उत्तमभ्राता मनुर्नाम्ना च तामसः ।
पृथुः ख्यातिर्नरः केतुरित्याद्या दश तत्सुताः ॥२७॥

caturtha uttama-bhrātā
manur nāmnā ca tāmasaḥ
pṛthuḥ khyātir naraḥ ketur
ity ādyā daśa tat-sutāḥ

caturtha - the fourth Manu; uttama-bhrātā - the brother of Uttama; manuḥ - became the Manu; nāmnā - celebrated by the name; ca - also; tāmasaḥ - Tāmasa; pṛthuḥ - Pṛthu; khyātiḥ - Khyāti; naraḥ - Nara; ketuḥ - Ketu; iti - thus; ādyāḥ - headed by; daśa - ten; tat-sutāḥ - sons of Tāmasa Manu.

Text

The brother of the third Manu, Uttama, was celebrated by the name Tāmasa, and he became the fourth Manu. Tāmasa had ten sons, headed by Pṛthu, Khyāti, Nara and Ketu.

Purport

Srimad Bhagavatam. Canto 8: Withdrawal of the Cosmic Creations

Chapter 1: The Manus, Administrators of the Universe. Text 27

The brother of the third Manu, Uttama, was celebrated by the name Tāmasa, and he became the fourth Manu. Tāmasa had ten sons, headed by Pṛthu, Khyāti, Nara and Ketu.