Horn, Sam. <br/><br/>
Concentration! :  how to focus for success / 
Sam Horn. 
 - Los Altos, Calif. :  Crisp Publications,  c1991. 
 - iii, 92 p. :  ill. ;  26 cm. 
<br/><br/><label>ISBN: </label>1560520736 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Attention.<br/>Mental discipline.<br/>Success--Psychological aspects.
<br/><br/><label>LC Class. No.: </label>BF637.S8  / H615 1991