Extraterrestrials where are they? 
edited by Michael H. Hart and Ben Zuckerman                                             
 - New York  Pergamon Press  1982 
 - ix, 182p. 
<br/><br/><label>ISBN: </label>0-08-026342-9 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Astronomy and astrophysics thesaurus<br/>Extraterrestrial life<br/>Origin of life
<br/><br/><label>Universal Decimal Class. No.: </label>52-37  / EXT