Armentrout, David& Patricia   <br/><br/>
Pulleys  

 - Florida:  Rourke Publishing;  2010. 
 - 24 Pages  Colour illustrations  26 cm 
 - Simple machines .
<br/><br/><label>ISBN: </label>9781606943892 
<br/><br/><label>Dewey Class. No.: </label>J 621.8 PULL