Geer, Helen Thornton <br/><br/>
Charging systems 

 - Chicago:   American Library Association,   1955 
 - xii, 177p.  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Library science
<br/><br/><label>Subjects--Index Terms: </label>Charging Computer 
<br/><br/><label>Universal Decimal Class. No.: </label>D 024.6  / J5.3