Wagenaar, Theodore C..
Practicing social research: guided activities to accompany "The practice of social research" /
Theodore C. Wagenaar, Earl Babbie 
. - 6th edition 
. - Belmont : Wadsworth Publishing Company,  1992 
. - viii, 319 p.  23 cm. 
<br/><label>  ISBN: </label>0-534-15577-4