Valmiki Ramayana Bala Kanda Sarga 45 Shloka 2
Original Shlokaअत्यद्भुतमिदं ब्रह्मन् कथितं परमं त्वया। गङ्गावतरणं पुण्यं सागरस्यापि पूरणम्।।1.45.2।।
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ब्रह्मन् O Knower of Brahma, त्वया by you, कथितम् is narrated, परमम् great, इदम् this, गङ्गावतरणम् descent of Ganga, पुण्यम् sacred, सागरस्य ocean's, पूरणम् replenishment, अत्यद्भुतम् exceedingly wonderful.
"O Knower of the Brahman this story narrated by you relating to the descent of the sacred Ganga and the fullness of the ocean (due to Ganga's fall) is very wonderful".