Koch, Helen Lois <br/><br/>
Twins and twin relations 
by Helen L. Koch. 
 - Chicago  University of Chicago Press  [1966] 
 - xvi, 302 p.  25 cm. 
<br/><br/>Bibliography: p. 281-292. 
<br/><br/><label>LCCN: </label>66020591  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Twins--Psychology.
<br/><br/><label>LC Class. No.: </label>BF723.T9  / K6 
<br/><br/><label>Dewey Class. No.: </label>155.444