Valmiki Ramayana Sundara Kanda Sarga 57 Shloka 29
Original Shlokaततस्तु वेगवांस्तस्य गिरेर्गिरिनिभः कपिः।।5.57.29।। निपपात महेन्द्रस्य शिखरे पादपाकुले।
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ततः thereafter, गिरिनिभः of mountain size, वेगवान् with great speed, कपिः monkey, तस्य on that, महेन्द्रस्य Mahendra's, गिरेः mountain, पादपाकुले full of trees, शिखरे summit, निपपात descended.
Thereafter the vanara, who resembled a mountain, descended with great speed on the summit of mount Mahendra full of trees.