Claridge, Gordon. <br/><br/>
Personality differences and biological variations :   a study of twins / 
by Gordon Claridge, Sandra Canter and W.I. Hume 
 - Oxford :    Pergamon Press,    1973. 
 - viii,175 p.    ill. ;    22 cm. 
 - International series of monographs in experimental psychology    vol.18. .
<br/><br/> Index. 
<br/><br/><label>ISBN: </label>0080171249 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Twins.<br/>Individuality.<br/>Variation (Biology).