National College of Edfrey50n       <br/><br/>
Young people's science encyclopedia v.21 
By the editors of the Young People's Science Encyclopedia 
 -  Children's Press  1993 
 - pg. 11-128 
<br/><br/> Aa-My 
<br/><br/><label>ISBN: </label>0-516-10122-6 
<br/><br/><label>Dewey Class. No.: </label>j503 You   25