Srimad-Bhagavatam: Canto 11 - Chapter 1 - Verse 19

Sanskrit:

तेषां नव नवद्वीपपतयोऽस्य समन्तत: ।कर्मतन्त्रप्रणेतार एकाशीतिर्द्विजातय: ॥ १९ ॥

ITRANS:

teṣāṁ nava nava-dvīpa-patayo ’sya samantataḥkarma-tantra-praṇetāraekāśītir dvijātayaḥ

Translation:

Nine of the remaining sons of Ṛṣabhadeva became the rulers of the nine islands of Bhārata-varṣa, and they exercised complete sovereignty over this planet. Eighty-one sons became twice-born brāhmaṇas and helped initiate the Vedic path of fruitive sacrifices [karma-kāṇḍa].

Purport:

The nine dvīpas, or islands, ruled by nine sons of Ṛṣabhadeva are the nine varṣas of Jambudvīpa, namely Bhārata, Kinnara, Hari, Kuru, Hiraṇmaya, Ramyaka, Ilāvṛta, Bhadrāśva and Ketumāla.