Perera, Nirmala. <br/><br/>
Grade 11 Science :  Work Book (2016 New Syllabus). 

 - 1st Ed. 
 - Colombo :  Jeya Book Centre,  2016. 
 - 136 P. 
<br/><br/><label>ISBN: </label>9789550137633 
<br/><br/><label>Dewey Class. No.: </label>500  / PER