Valmiki Ramayana Yuddha Kanda Sarga 30 Shloka 28
Original Shlokaपुत्त्रोदशरथस्यैषसिंहसंहनोयुवा । दूषणोनिहतोयेनखरश्चत्रिशिरास्तथा ।।6.30.28।।
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सिंहसंहनन built like lion in form, एष that, युवा young one, दशरथस्य Dasaratha's, पुत्त्र son, त्रिशिरा Trisira.
"That young one whose build is like a lion is Dasaratha's son who slayed Dushana, even Khara, like wise Trisira."