Valmiki Ramayana Sundara Kanda Sarga 33 Shloka 18
Original Shlokaतत्र त्रयोदशे वर्षे राज्येनेक्ष्वाकुनन्दनम्।।5.33.18।। अभिषेचयितुं राजा सोपाध्यायः प्रचक्रमे।
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ततः then, त्रयोदशे in the thirteenth, वर्षे in the year, सोपाध्यायः with his preceptor, राजा the king, इक्ष्वाकुनन्दनम् delight of the Ikshvakus, राज्येन in the kingdom, अभिषेचयितुम् to coronate, प्रचक्रमे arranged.
"Then in the thirteenth year king Dasaratha along with the royal preceptor arranged to coronate Rama, delight of the Ikshvaku family, in the kingdom.