Valmiki Ramayana Kishkindha Kanda Sarga 12 Shloka 38
Original Shlokaअभिज्ञानं कुरुष्व त्वमात्मनो वानरेश्वर। येन त्वामभिजानीयां द्वन्द्वयुद्धमुपागतम्4.12.38।।
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वानरेश्वर lord of monkeys, द्वन्द्वयुद्धम् duel, उपागतम् has come, त्वाम् you, येन by which, अभिजानीयाम् I may recognise you, अभिज्ञानम् an identification, आत्मनः you, कुरुष्व may put on.
'O lord of monkeys while you both are engaged in a duel wear some identification mark by which I can recognise you.