Hartree, Douglas R. (Douglas Rayner), 1897-1958.  Hartree, Douglas R. (Douglas Rayner), 1897-1958. <br/><br/>
Calculating instruments and machines. 

 - Cambridge [England] :  University Press,  1950. 
<br/><br/>Bibliography: p. 131-134. 
<br/><br/><label>LCCN: </label>51021381 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Calculators.<br/>Mathematical instrumens.
<br/><br/><label>LC Class. No.: </label>QA85  / .H29 1950 
<br/><br/><label>Dewey Class. No.: </label>510.78