Who was the author of Rajtarangini?

Kalhana authored the original core text of Rajatarangini in the 12th century covering early chronicles of Kashmir. Later, historians Jonaraja, Srivara, and Prajyabhatta officially extended and recorded successive continuations (Dvitiya, Tritiya, and Chaturthi Rajatarangini) across later regimes, making all of them authors within the historical series.