OPEN University of Sri Lanka <br/><br/>
Course of study leading to the degree of bachelor of science-level 3BTU 1201: pl 

 - Nugegoda  The Open University of Sri Lanka  1984 
 - 156 p. 
<br/><br/><label>ISBN: </label>139146 
<br/><br/><label>Dewey Class. No.: </label>588  / OPE