Selwyn, E. W. H. <br/><br/>
Theory of lenses 
E. W. H. Selwyn 
 - London  The Institute of Physics  1955 
 - 62p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Astronomy and Astrophysics Thesaurus<br/>Optics
<br/><br/><label>Universal Decimal Class. No.: </label>535.316  / SEL