Valmiki Ramayana Kishkindha Kanda Sarga 41 Shloka 40
Original Shlokaतं च देशमतिक्रम्य महानृषभसंस्थितः।।4.41.40।। सर्वरत्नमयः श्रीमान् ऋषभो नाम पर्वतः।
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तं देशम् that place, अतिक्रम्य after crossing, ऋषभसंस्थितः of the size of a bull, सर्वरत्नमयः filled with all gems, श्रीमान् rich, ऋषभोनाम named Rishaba, महान् huge, पर्वतःmountain
'With this place passed, you will see a huge mountain named Rishaba of the size of a bull filled with all gems.