Saghir Iqbal,  PhD in Education,  2014, <br/><br/>
Effective of problem based learning units on students academic achievement in the subject of science at elementary level 
/ Saghir Iqbal 
 - Lahore :  Division of Education, Univeristy of Education,  2014 
 - 148 p. 
<br/><br/><label>ISBN: </label>(hbk) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Education--Academic Achievement--Science--Elementary Level
<br/><br/><label>Dewey Class. No.: </label>372.5  / Ef361