Essentials of behavioural research : methods and data analysis/ 
Robert, Rosenthal 
 - Oxford:  Blackwelll;  1993. 
 - xvi,510P.: 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Social sciences
<br/><br/><label>Dewey Class. No.: </label>300.72   / ROB N93R