Valmiki Ramayana Sundara Kanda Sarga 49 Shloka 16
Original Shlokaभ्राजमानं ततो दृष्ट्वा हनुमान्राक्षसेश्वरम्। मनसा चिन्तयामास तेजसा तस्य मोहितः।।5.49.16।।
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ततः then, हनुमान् Hanuman, भ्राजमानम् splendid, राक्षसेश्वरम् lord of ogres, दृष्ट्वा after seeing, तस्य his, तेजसा by splendour, मोहितः dismayed, मनसा in mind, चिन्तयामास started thinking.
Seeing the splendour of the lord of demons, Hanuman was dimayed and started thinking thus: