Block 4 water resources :  science, a second level course/ 
prepared by an Open University Course Team. 
 - Walton Hall, Milton Keynes :  The Open University,  1986. 
 - 96 p. :  ill. (some col.), maps (some col.) ;  30 cm. 
 - S238 the earth's physical resources. .
<br/><br/><label>ISBN: </label>0335161596 (pbk.) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Water resources development.