Valmiki Ramayana Yuddha Kanda Sarga 93 Shloka 28
Original Shlokaमयावर्षसहस्राणिचरित्वापरमंतपः ।।6.93.28।। तेषुतेष्ववकाशेषुस्वयम्भूःपरितोषितः ।
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मया by me, वर्षसहस्राणि thousand years, परमम् supreme, तपः austerities, चरित्वा having done, तेषुतेषु several times, अवकाशेषु in that occasion, स्वयम्भूः selfborn creator, परितोषितःpleased him
'I have done penance for thousands of years several times and am a pleased selfborn creator'.