Valmiki Ramayana Bala Kanda Sarga 45 Shloka 8
Original Shlokaतस्य तद्वचनं श्रुत्वा राघवस्य महात्मन:। सन्तारं कारयामास सर्षिसङ्घ स्सराघव:।।1.45.8।।
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तस्य महात्मन: of that illustrious, राघवस्य Rama's, तत् वचनम् those words, श्रुत्वा having heard, सर्षिसङ्घ: accompanied by hosts of sages, सराघव: together with Rama and Lakshmana, सन्तारम् to cross over, कारयामास made (arrangements).
Hearing the words of noble Rama, he (Viswamitra), accompanied by hosts of sages besides Rama and Lakshmana made arrangements to cross (the river).