Murphy, Patricia J.  1963 <br/><br/>
Push and pull 
Patricia J Murphy 
 - ed. 
 - [S.l.]  Children's Press  2002 
 - 31 p. 
 - Rookie read-about science .
 - Rookie read-about science .
<br/><br/><label>ISBN: </label>0329304992 0516225510 0516268643 (pbk.) 1404638164