Valmiki Ramayana Yuddha Kanda Sarga 70 Shloka 47
Original Shlokaस तस्यशीर्षाण्यसिनाशितेनकिरीटजुष्टानिसकुण्डलानि । क्रुद्धःप्रचिच्छेदसुतोऽनिलस्यत्वष्टुस्सुतस्येवशिरांसिशक्रः ।।6.70.47।।
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क्रुद्धः enraged, सः he, अनिलस्यसुतः wind god's son, तस्य his, कीरीटजुष्टानि along with crown, सकुण्डलानि and earrings, शीर्षाणि three heads (of Vishwarupa), शक्रः Indra, त्वष्टुः Twashsta's, सुतस्य son's, शिरांसिइव three heads like that, शितेन sharp, असिना cut off, प्रचिच्छेद severed.
Enraged wind god's son, cut off the three heads of Trisira adorned with earrings just as Indra cut off the heads of Vishwarupa, son of Twashta.