Valmiki Ramayana Sundara Kanda Sarga 10 Shloka 21
Original Shlokaददर्श स कपिस्तत्र बाहू शयनसंस्थितौ। मन्दरस्यांतरे सुप्तौ महाही रुषिताविव।।5.10.21।।
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सः कपिः that vanara, तत्र there, मन्दरस्य mount Mandara's, अन्तरे in the cave, सुप्तौ asleep, रुषितौ angry, महाही इव like two serpents, शयनसंस्थितौ placed on the bed, बाहू two arms, ददर्श saw.
The vanara, gazed at the arms of Ravana placed on the couch that appeared like two angry snakes asleep in a cave on (the lap) of mount Mandara.