Leedy, Paul D. <br/><br/>
Practical research :  planning and design / 
Paul D. Leedy, Jeanne Ellis Ormrod. 
 - 9th  ed. 
 - Boston :  Pearson,  2010. 
 - xvii, 336  p. 
<br/><br/><label>ISBN: </label>0131365667 : 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Research--Methodology.