What is "kalhana"

Kalhana (sometimes spelled Kalhan or Kalhan'a) (c. 12th century), a Kashmiri, was the author of Rajatarangini (River of Kings), an account of the history of Kashmir. He wrote the work in Sanskrit between 1148 and 1149. All information regarding his life has to be deduced from his own writing, a major scholar of which is Mark Aurel Stein. Robin Donkin has argued that with the exception of Kalhana, "there are no [native Indian] literary works with a developed sense of chronology, or indeed much sense of place, before the thirteenth century".