Valmiki Ramayana Sundara Kanda Sarga 49 Shloka 15
Original Shlokaस तैस्सम्पीड्यमानोऽपि रक्षोभिर्भीमविक्रमैः। विस्मयं परमं गत्वा रक्षोधिपमवैक्षत।।5.49.15।।
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सः he, भीमविक्रमैः by those of fierce valour, रक्षोभिः by ogres, सम्पीड्यमानोऽपि even though pressed hard, परमम् great, विस्मयम् wonder, गत्वा experiencing, रक्षोधिपम् king of demons, अवैक्षत saw.
Hanuman looked at the demon king with great amazement even while he was dealt harshly by the demons of fierce valour.