Valmiki Ramayana Kishkindha Kanda Sarga 35 Shloka 7
Original Shlokaघृताच्यां किल संसक्तो दशवर्षाणि लक्ष्मण। अहोऽमन्यत धर्मात्मा विश्वामित्रो महामुनिः।।4.35.7।।
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लक्ष्मण Lakshmana, धर्मात्मा great self, महामुनिः great sage, विश्वामित्रः Visvamitra, दश ten, वर्षाणि years, घृताच्याम् with an apsara Gritachi, संसक्तः in union, अह one day, अमन्यत thought, किल indeed.
'O Lakshmana great sage Visvamitra was in union with an apsara Gritachi for ten years and felt it was just one day indeed