Sociological research methods  : an introduction 
/ ed.by Martin Bulmer,... 
. - London  : Martin Bulmer, 1977
. - XII - 363 p.  ; 23 cm. 
<br/><br/>Bibliogr. 
<br/><br/><label>ISBN: </label>0333212525  0333212738 
<br/><br/><label>Source: </label>060271 
<br/><br/><label>Universal Decimal Class. No.: </label>301.