OPEN University of Sri Lanka <br/><br/>
Course of study leading to the degree of bachelor of science level 4 PSU 2115 ph 

 - Nugegoda  The Open University of Sri Lanka  1987 
 - 49 p. 
<br/><br/><label>ISBN: </label>103038 
<br/><br/><label>Dewey Class. No.: </label>541.363  / OPE