Hayes, Richard J. <br/><br/>
Cluster randomised trials 

 - Boca Raton  CRC Press  2009 
 - xxii, 315p. 
<br/><br/><label>ISBN: </label>978-1-58488-816-1 
<br/><br/><label>Subjects--Index Terms: </label>Clinical trials Cluster analysis 
<br/><br/><label>Dewey Class. No.: </label>51-7  / HAY