International understanding :  as an integral part of the school curriculum : research in comparative education. 

 - Paris :  Geneva :  UNESCO;  IBE,  1968. 
 - l, 240 p. 
 - UNESCO-BIE Publications; 312 .
<br/><br/><label>No. de Clasificación Universal Decimal: </label>37.017.7 (100)=20 "1968" INT.