Pam American Health Organization <br/><br/>
Guide for the identification of the snail intermediate hosts of schistosomiasis in the Americas  Pam American Health Organization World Health Organization. 

 - Washington  Pam American Health Organization, World Health Organization 
 - ix, 122p., ill. 24cm. 
<br/><br/><label>Dewey Class. No.: </label>616.963,  / G95G