International encyclopedia of education  V.4:F-H 
ed. by Tosten Husen, T.Neville Postlethwaite. 
 - Oxford  Pergamon Press  1985 
 - ix, 564p. 
<br/><br/><label>ISBN: </label>0080281192 
<br/><br/><label>Dewey Class. No.: </label>370.321  / N85.4