Valmiki Ramayana Ayodhya Kanda Sarga 110 Shloka 12
Original Shlokaत्रिशङ्कोरभवत्सूनुर्दुन्धुमारो महायशाः।।2.110.12।। दुन्धुमारान्महातेजा युवनाश्वो व्यजायत।
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त्रिशङ्कोः to Trishanku, महायशाः of illustrious, दुन्धुमारः Dundhumara, सूनुः as son, अभवत् became, दुन्धुमारात् from Dundhumara, महातेजाः exceedingly powerful, युवनाश्वः Yuvanaswa, व्यजायत was born.
Trishanku's son was illustrious Dundhumara, father of the exceedingly powerful Yuvanaswa.