Hoover, David S. <br/><br/>
The development and evaluation of an automated reflectance microscope system for the petrographic characterization of bituminous coals / 
by David Samuel Hoover 
 - 3 microfiches ;  11 x 15 cm. 
<br/><br/>Thesis (Ph.D.)-Pennsylvania State University, 1980 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Petrographic microscope.