Seasonality and Health :  A Study of the social - economic environment of ill - health in five location /  English. 
Perera, P.D.A., Fernando, J., Fernando, E. 
 - Colombo :  Maga institute,  1988. 
 - 135 p.:  ill. maps, diagrams ;  28cm 
<br/><br/><label>Dewey Class. No.: </label>X55.588:33  / MAR