佛祖統紀 2.38

2.38

Fortieth year (wuchen): The Prince was fifteen years old. The King assembled his ministers, minor kings, ṛṣis, and brāhmaṇas, who all gathered like clouds. On the eighth day of the second month, using vessels of the seven treasures, they filled them with water from the four great oceans, each bearing them on their heads and transmitting them to the King. They anointed the Prince's crown, conferred the seven-jewel seal, and installed him as Crown Prince. At that time, eight kings of other realms also installed their crown princes on the same day (Sūtra on Cause and Effect).