Scientific American 236 

 - New York  Sciam  Fev. 1977 
 - 138 
 - 20100702 
 - Scientific American  236 .
<br/><br/><label>ISSN: </label>1679-656X 
<br/><br/><label>Dewey Class. No.: </label>SAM 2010  / 2010