OPEN University of Sri Lanka <br/><br/>
Course of study leading to the degree of bachelor of science level IV BTU 2112: 

 - Nugegoda  The Open University of Sri Lanka  1996 
 - 151 p. 
<br/><br/><label>ISBN: </label>139212 
<br/><br/><label>Dewey Class. No.: </label>581.15  / OPE