Osborn, Roger. <br/><br/>
Understanding the Number System / 
Roger Osborn, M.Vere De Vault, Claude C.Boyd & W.Robert Houston. 
 - 1st ed. / 
 - Columbus :  Charles E.Merrill Books,Inc. ,  1968. 
 - 189p. :  ill ;  22cm . 
<br/><br/>Index 
<br/><br/><label>Subjects--Index Terms: </label>Mathematics G-Mathematics 
<br/><br/><label>Dewey Class. No.: </label>511  / Os 2 Un