Valmiki Ramayana Yuddha Kanda Sarga 20 Shloka 12
Original Shlokaनहीयंहरिभिर्लङ्काशक्याप्राप्तुंकथञ्चन । देवैरपिसगन्धर्वैःकिंपुनर्नरवानरैः ।।6.20.12।।
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इयंलङ्का: in this Lanka, हरिभिः even Vanaras, प्राप्तुम् to get here, नशक्याहि: is not possible, सगन्धर्वैः even Gandharvas, देवैरपि: even Devas also, नरवानरैः of humans and Vanaras, किंपुनः what to say.
"It is not possible for Vanaras to get here even for Gandharvas or Devas also. What to say of humans and Vanaras? (You may tell this to Sugriva)."