Valmiki Ramayana Bala Kanda Sarga 39 Shloka 14
Original Shlokaएकैकयोजनं पुत्रा विस्तारमधिगच्छत। यावत्तुरगसन्दर्श: तावत् खनत मेदिनीम्। तं चैव हयहर्तारं मार्गमाणा ममाज्ञया।।1.39.14।।
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पुत्रा: O Sons, एकैकयोजनम् yojana by yojana, विस्तारम् length and breadth of earth, अधिगच्छत you may acquire, मम my, आज्ञया by command, तं हयहर्तारम् that thief of horse, मार्गमाणा: while search for, तुरगसन्दर्श: finding the horse, यावत् तावत् till such time, मेदिनीम् earth, खनत excavate.
'O sons, acquiring yojana by yojana the length and breadth of the earth, search for the thief of the horse. Excavate the earth till the time the horse is found. This is my command'.