Valmiki Ramayana Bala Kanda Sarga 42 Shloka 1
Original Shlokaकालधर्मं गते राम सगरे प्रकृतीजना:। राजानं रोचयामासुरंशुमन्तं सुधार्मिकम्।।1.42.1।।
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राम O Rama, सगरे when king Sagara, कालधर्मम् duty of nature, death, गते obtained, प्रकृतीजना: ministers and subjects, सुधार्मिकम् highly virtuous, अंशुमन्तम् Anshuman, राजानम् as king, रोचयामासु: accepted.
"O Rama when Sagara died, the subjects installed the highly virtuous Anshuman as king. Anshuman performs penance to bring Ganga to the earth-- Bhagiratha follows --receives boon from Brahma--Brahma informs Anshuman that only lord Siva is capable to hold Ganga.