Morgan, Stephen L. <br/><br/>
Counterfactuals and casual inference :  methods and principles for social research 
/ Stephen L. Morgan and Christopher Winship 
 - Cambridge :  Cambridge University Press,  c2007 
 - xi, 319 p. :  ill. ;  24 cm 
<br/><br/>Includes references and index 
<br/><br/><br/>eng. 
<br/><br/><label>ISBN: </label>9780521856157  TZS 45,458/= 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Research 
<br/><br/><label>Dewey Class. No.: </label>300.72 MOR