Mathematics Changes Gear 

 - London:  Heinemann Educational Books Ltd,  1975. 
 - 47p.;  ill.  18cm 
<br/><br/><label>ISBN: </label>0435516957 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Basic Mathematics
<br/><br/><label>Dewey Class. No.: </label>510  / MAT