Valmiki Ramayana Sundara Kanda Sarga 9 Shloka 9
Original Shlokaया च राज्ञः कुबेरस्य यमस्य वरुणस्य च। तादृशी तद्विशिष्टा वा ऋद्धी रक्षोगृहेष्विह।।5.9.9।।
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राज्ञः of the king, कुबेरस्य Kubera's, या whatever, यमस्य Yama's, वरुणस्य Varuna's, च and, या whatever, तादृशी such, तद्विशिष्टा वा or more exquisite than, ऋद्धि: wealth इह here, रक्षोगृहेषु in the houses of demons.
The wealth stored in Ravana's palace was akin to what lay in the palaces of Kubera, Yama or Varuna, and ever more exquisite.