Retherford, Robert D. <br/><br/>
Birth order and intelligence :  further tests of the confluence model / 
Robert D. Retherford, William H. Sewell 
 - Honolulu :  East-West Population Institute,  1991 
 - p. 141-158 ;  24 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Birth order<br/>Children--Intelligence testing