00416nam a22001217a 4500008004100000040005500041080002500096245008200121260005200203300000900255650001400264653001600278230419b        |||||||| |||| 00| 0 eng d  aNational Science LibrarycNational Science Library  a616.995.13:594.3bK5  aSnail control in the prevention of belharziasis c/ World Health Organization  aGeneva:  bWorld Health Organization,    c1965  a59p.  2Economics  aEnvironment