Educational applications of videotex systems :  international review study. 

 - Hungary :  Hungarian National Commission for UNESCO,  1986. 
 - pág. irregular. ;  lamns. 
<br/><br/><label>ISBN: </label>9634411290 
<br/><br/><label>No. de Clasificación Universal Decimal: </label>371.68 =20 "1986" EDU.