Bausch <br/><br/>
Certified precision diffraction gratings 
Bausch and  Lomb                                                
 - New York  Bausch and Lomb  1981 
 - i, 22p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Astronomical instrumentation<br/>Astronomy and astrophysics thesaurus
<br/><br/><label>Universal Decimal Class. No.: </label>520.9  / BAU