LANGRIDGE,D.W <br/><br/>
Classification: Its kinds,Elements,Systerm and Applications 

 - London.  Bower-Saur, GB  1992 
 - (x),84p. 
<br/><br/><label>ISBN: </label>862916224 
<br/><br/><label>Dewey Class. No.: </label>025.4'2