Valmiki Ramayana Bala Kanda Sarga 11 Shloka 10
Original Shlokaपुत्राश्चास्य भविष्यन्ति चत्वारोऽमितविक्रमा:। वंशप्रतिष्ठानकरास्सर्वलोकेषु विश्रुता:।।1.11.10।।
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अस्य to him, अमितविक्रमा: men of immense prowess, वंशप्रतिष्ठानकरा: bringing glory and fame to their dynasty, सर्वलोकेषु in all the worlds, विश्रुता: renowned, चत्वार: four, पुत्रा: sons, भविष्यन्ति will be born.
Four sons of immense prowess would be born to him bringing glory and fame to their dynasty. They would be renowned in all the worlds.