Friis, Robert H. <br/><br/>
Epidemiology for Public Health Practice. 

 - 2nd ed. 
 - 1999  An Aspen PublicationUnited states of america 
 - viii,506p.22 cm 
<br/><br/><label>ISBN: </label>9780834211780 
<br/><br/><label>Dewey Class. No.: </label>614.4