Kerlinger, Fred N <br/><br/>
Foundations of behavioral research 

 - 2nd ed. 
 - Delhi  Surjeet publications  1964 
 - xx, 741p.; 22cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Approach science<br/>Knowledge - research methods<br/>Probability - sampling<br/>Sets, relations - variance