Valmiki Ramayana Kishkindha Kanda Sarga 11 Shloka 42
Original Shlokaतयोस्तु क्रोधसंरम्भात्परस्परजयैषिणोः। युद्धं समभवद्घोरं दुन्दुभेर्वानरस्यच4.11.42।।
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क्रोधसंरम्भात् highly agitated in anger, परस्परजयैषिणोः of both trying to win over the other, तयोः of both, दुन्दुभेः for Dundubhi, वानरस्य च and of the monkey, घोरम् terrific, युद्धम् combat, समभवत् took place.
'Each one of them was highly agitated and angry trying to win over the other. A terrific fight took place between Dundubhi and Vali.