Kaddoura  Sam <br/><br/>
ECHO Made Easy 

 - 2nd  edition 
 -  Churchill Livingstone  2009 
 - 1-232 pages with index 
<br/><br/><label>ISBN: </label>978-0-443-10364-3 
<br/><br/><label>Nat. Bib. No.: </label>004694 
<br/><br/><label>Dewey Class. No.: </label>616.12-073.97 K12