Valmiki Ramayana Sundara Kanda Sarga 9 Shloka 8
Original Shlokaया हि वैश्रवणे लक्ष्मीर्या चेन्द्रे हरिवाहने। सा रावणगृहे सर्वा नित्यमेवानपायिनी।।5.9.8।।
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वैश्रवणे by Vaisravana, या whatever, लक्ष्मीः wealth हरिवाहने on greenish horse, the mount, इन्द्रे च of Indra, या as much, सा that, सर्वा everything, रावणगृहे in the residence of Ravana, नित्यमेव always, अनपायिनी present.
Whatever wealth was possessed by Vaisravana (Kubera, the son of sage Vishrava) and also Indra who rides the Ucchaisrava green horse, was there in the palace of Ravana.