Valmiki Ramayana Bala Kanda Sarga 52 Shloka 12
Original Shlokaततो वसिष्ठो भगवान् कथाऽन्ते रघुनन्दन । विश्वामित्रमिदं वाक्यमुवाच प्रहसन्निव।।1.52.12।।
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रघुनन्दन O Descendent of Raghu, तत: then, भगवान् venerable, वसिष्ठ: Vasishta, कथाऽन्ते after the conversation had ended, प्रहसन्निव smiling as it were, विश्वामित्रम् addressing Viswamitra, इदं this, वाक्यम् word, उवाच spoke.
O Descendent of Raghu at the end of the conversation, venerable Vasishta, smiling as it were said to Viswamitra