Van Dalen Deobold B <br/><br/>
Understanding educational research: An introduction 

 - 4 
 - New York, USA  McGraw-Hill  1979 
 - xii,547p. 
<br/><br/><label>ISBN: </label>0-07-066883-3 
<br/><br/><label>Source: </label>Reference 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Research methods