Valmiki Ramayana Bala Kanda Sarga 41 Shloka 6
Original Shlokaस खातं पितृभिर्मार्गमन्तर्भौमं महात्मभि:। प्रापद्यत नरश्रेष्ठ तेन राज्ञाऽभिचोदित:।।1.41.6।।
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नरश्रेष्ठ O Best among men, स: he, राज्ञा by king, अभिचोदित: directed, महात्मभि: by the noble, पितृभि: uncles, अन्तर्भौमम् in the depths of earth, खातम् dug, मार्गम् path, प्रापद्यत followed.
O Best among men directed by the king (Sagara), Anshuman followed the path taken by his noble uncles into the depths of the earth.