Valmiki Ramayana Yuddha Kanda Sarga 45 Shloka 5
Original Shlokaतेषांवेगवतांवेगमिषुभिर्वेगवत्तरैः । अस्त्रवित्परमास्तैरैस्तुवारयामासरावणिः ।।6.45.5।।
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अस्त्रवित् skilled in the use of weapons, रावणिः Ravana's son, परमास्तै: expert in mystic weapons, वेगवत्तरैः endowed with speed, इषुभिः arrows, वेगवताम् charged with energy, तेषाम् them, वेगम् swiftly, वारयामास prohibited
Ravana's son being skilled in the use of weapons and an expert in mystic powers, he prohibited the speed of the Vanaras with his swift arrows.