Valmiki Ramayana Sundara Kanda Sarga 23 Shloka 6
Original Shlokaप्रजापतीनां षण्णां तु चतुर्थो यः प्रजापतिः। मानसो ब्रह्मणः पुत्रः पुलस्त्य इति विश्रुतः।।5.23.6।।
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षण्णाम् of the six, प्रजापतीनाम् of Prajapatis, यः he who was, चतुर्थः fourth, प्रजापतिः, ब्रह्मणः Brahma, मानसः born out of mind, पुत्रः a son, पुलस्त्यः Pulastya, इति thus, विश्रुतः very famous.
'The mindborn son of Brahma is well known as Paulastya. He was the fourth among the six Prajapatis (Maricha, Atri, Angira, Pulastya, Plaha, Kratu).