Lens, Al <br/><br/>
Optics, retinoscopy, and refractometry 

 - 2nd ed. 
 - Slack Incorporated, Vancouver  2006 
 - vii,130 
<br/><br/><label>ISBN: </label>1-55642-748-4 
<br/><br/><label>Dewey Class. No.: </label>617.755 Len