Valmiki Ramayana Yuddha Kanda Sarga 42 Shloka 11
Original Shlokaशिखरैर्विकिरामैनांलङ्कांमुष्टिभिरेववा । इतिस्मदधिरेसर्वेमनांसिहरियूथपाः ।।6.42.11।।
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हरियूथपाः Vanara troops, लङ्कां Lanka, शिखरैर्विकिरामैनां with mountain peaks, मुष्टिभिरेववा or with fists, इति this, स्मदधिरे will crush, सर्वे all, मनांसि thought.
The monkey troops thought of crushing Lanka with their fists and mountain peaks.