Valmiki Ramayana Kishkindha Kanda Sarga 51 Shloka 11
Original Shlokaपुरा दानवमुख्यानां विश्वकर्मा बभूव ह।।4.51.11।। येनेदं काञ्चनं दिव्यं निर्मितं भवनोत्तमम्।
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येन by whomsoever, काञ्चनम् golden, दिव्यम् wonderful, इदम् this, भवनोत्तमम् best of mansions, निर्मितम् constructed, पुरा earlier, दानवमुख्यानाम् chiefs of demons, विश्वकर्मा Visvakarma, बभूव existed.
This best of wonderful mansions has been constructed earlier by Visvakarma, the chief (architect) of the demons.