Valmiki Ramayana Yuddha Kanda Sarga 24 Shloka 21
Original Shlokaशिखरैर्विकिरामैनांलङ्कांमुष्टभिरेववा । इतिस्मदधिरेसर्वेमनांसिहरिपुङ्गवाः ।।6.24.21।।
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एनाम् thus, लङ्काम् that Lanka, शिखरैः with peaks, मुष्टिभिरेववा or with bare fists, विकिराम crush it to powder, इतिसर्वे thus all, हरिपुङ्गवाः Vanara leaders, मनांसि determined in their mind, दधिरे hold, स्म indeed.
Thus resolved the Vanara leaders in their mind to crush Lanka with its mountain peaks into powder with their bare fists, indeed.