Srimad-Bhagavatam: Canto 5 - Chapter 1 - Verse 26
Sanskrit:
एतेषां वर्षमर्यादागिरयो नद्यश्च सप्त सप्तैव ईशान उरुशृङ्गो बलभद्र: शतकेसर: सहस्रस्रोतो देवपालो महानस इति अनघाऽऽयुर्दा उभयस्पृष्टिरपराजिता पञ्चपदी सहस्रस्रुतिर्निजधृतिरिति ॥ २६ ॥
ITRANS:
eteṣāṁ varṣa-maryādā-girayo nadyaś ca sapta saptaiva īśāna uruśṛṅgo balabhadraḥ śatakesaraḥ sahasrasroto devapālo mahānasa iti anaghāyurdā ubhayaspṛṣṭir aparājitā pañcapadī sahasrasrutir nijadhṛtir iti.
Translation:
For these lands also, there are seven boundary mountains and seven rivers. The mountains are Īśāna, Uruśṛṅga, Balabhadra, Śatakesara, Sahasrasrota, Devapāla and Mahānasa. The rivers are Anaghā, Āyurdā, Ubhayaspṛṣṭi, Aparājitā, Pañcapadī, Sahasra-śruti and Nijadhṛti.