Backer, Joseph, L. <br/><br/>
Record book exlploring physical science 

 - American:  Allyn and bacon inc,  1977. 
 - 326p,  ill.  28cm 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mathematics
<br/><br/><label>Dewey Class. No.: </label>520.2  / BEC