Valmiki Ramayana Sundara Kanda Sarga 68 Shloka 24
Original Shlokaमम पृष्ठगतौ तौ च चन्द्रसूर्याविवोदितौ। त्वत्सकाशं महाभागे नृसिंहावागमिष्यतः।।5.68.24।।
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महाभागे O noble lady, नृसिंहौ lions among men, तौ च they both, मम my, पृष्ठगतौ on back, उदितौ ascend, चन्द्रसूर्याविव like Sun and Moon, त्वत्सकाशम् newly risen, आगमिष्यतः will reach here.
'O noble lady the lions among men, Rama and Lakshmana who resemble Sun and Moon will ascend on my back and reach here.