Śrīmad-Bhāgavatam · Text 6.10.16
Who is speaking and story frame
तत: सुराणामसुरै रण: परमदारुण: ।
त्रेतामुखे
नर्मदायामभवत्प्रथमे युगे ॥ १६ ॥
tataḥ surāṇām asurai
raṇaḥ parama-dāruṇaḥ
tretā-mukhe narmadāyām
abhavat prathame yuge
Thereafter, at the end of Satya-yuga and the beginning of Tretā-yuga, a fierce battle took place between the demigods and the demons on the bank of the Narmadā.
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