Valmiki Ramayana Yuddha Kanda Sarga 103 Shloka 37
Original Shlokaदशास्योविंशतिभुजःप्रगृहीतशरासनः ।।6.103.37।। अदृशास्यःदशग्रीवःमैनाकःपर्वतःइव
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दशास्यः ten heads, विंशतिभुजः twenty arms, प्रगृहीतशरासनः seizing hold of bow, दशग्रीवः ten headed, मैनाकःपर्वतः इव like Mynaka mountain, अदृश्यत appeared
Ravana with ten heads and twenty arms seizing his bow appeared like the Mynaka mountain.