Posavac, Emil J. <br/><br/>
Program evaluation :  methods and case studies / 
Emil J. Posavac, Raymond G. Carey. 
 - 4th ed. 
 - Englewood Cliffs, N.J. :  Prentice-Hall,  1992. 
 - 332 p. :  ill. ;  24 cm. 
<br/><br/>p. 303-317 
<br/><br/><label>ISBN: </label>0136781292 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Evaluation research (Social action programs)--United States.