Gopinathan, R. <br/><br/>
Keralattanima  Keralathinte samoohika, samskarika, rashtreeyacharitram, naattuvijnaneeyam, sahityam, kalakal ennivayiloode BC 1000 muthal AD 700 vare / 

 - Thiruvananthapuram :  Heritage Studies ,  2010. 
 - 536 p.