Perera <br/><br/>
Science Grade 11  Work book Part 2 
Nirmala Perera 
 - Colombo 11  Jaya Book centre  2016 
 - 136 
<br/><br/><label>ISBN: </label>9789550137633 
<br/><br/><label>ISSN: </label>
<br/><br/><label>Dewey Class. No.: </label>500  / PER