Purposive systems  proceedings of 1st annual symposium of theAmerican Society for Cybernetics. 
ed. by Heinzvon Foerster [etal..] 
 - New York  Spartan Books  1968 
 - xvi, 179p. 
<br/><br/><label>LCCN: </label>68-56435 
<br/><br/><label>Dewey Class. No.: </label>001.53  / N68