Parkyn, George W <br/><br/>
Towards a conceptual model of life-long education / 
George W. Parkyn. 
 - Paris :  UNESCO,  1973. 
 - 54 p. 
 - Educational studies and documents; new series ;  12. .
<br/><br/><label>ISBN: </label>9231011170 
<br/><br/><label>No. de Clasificación Universal Decimal: </label>374.1 =20 PAR No. 12.