Valmiki Ramayana Bala Kanda Sarga 21 Shloka 17
Original Shlokaसुप्रभाऽजनयच्चापि पुत्रान्पञ्चाशतं पुन:। संहारान्नामदुर्धर्षान् दुराक्रामान् बलीयस:।।1.21.17।।
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सुप्रभापि Suprabha also, दुर्धर्षान् unassailable, दुराक्रमान् invincible, बलीयस: morepowerful, संहारान् नाम Samhara by name पुन: still, पञ्चाशतम् fifty, पुत्रान् sons, अजनयत् gave birth.
Suprabha gave birth to another fifty sons named Samharas who are unassailable, invincible and more powerful.