Valmiki Ramayana Kishkindha Kanda Sarga 40 Shloka 57
Original Shlokaतत्रपूर्वं पदं कृत्वा पुरा विष्णुस्त्रिविक्रमे।।4.40.57।। द्वितीयं शिखरे मेरोश्चकार पुरुषोत्तमः।
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पुरुषोत्तमः supreme being, विष्णुः Visnu, पुरा formerly, त्रिविक्रमे taking three strides, पूर्वम् first, तत्र there, पदम् foot, कृत्वा after that, द्वितीयम् second, मेरोः Meru's, शिखरे on the peak, चकार placed.
'When the supreme being, Visnu took his three strides as Lord Vamana, he placed his first foot on this peak and the second on the peak of mount Meru.