Welford, W. T <br/><br/>
Aberrations of the symmetrical optical system / 
W. T. Welford 
 - London :  Academic Press,  1974 
 - ix, 240 p. :  ill. ;  24 cm. 
<br/><br/>Includes bibliographical references and indexes. 
<br/><br/><label>ISBN: </label>0127420509 
<br/><br/><label>LCCN: </label>74-005674 //r86 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Optical instruments--Design and construction<br/>Aberration<br/>Optics, Geometrical