Sumner, R. <br/><br/>
Achievement in secondary school :  attitudes, personality and school success / 
R. Sumner and F. W. Warburton. 
 - London :  NFER,  1972. 
 - 208 p. :  il. 
<br/><br/><label>ISBN: </label>901225762 
<br/><br/><label>Encabezamiento--Tema: </label><br/>CONDUCTA ESTUDIANTIL<br/>EDUCACION SECUNDARIA ---INVESTIGACION