"Results of a study in which particular account is taken of certain major items of information which are both useful and indispensable to the study of the relationships between national development and the development of the communication media — The author has tried to see to what extent certain items of information, previously considered basic to studies of this subject, are shown to be inadequate for a serious study of the question — The various factors, the correlation between them and their interdependence should be studied more closely — The author gives details of the results of a study made in the United States; he attempts to compare the data for 5 different countries (United States — Japan — Finland — Mexico — Costa Rica)." (Jean-Marie Van Bol, Abdelfattah Fakhfakh: The use of mass media in the developing countries. Brussels: CIDESA, 1971 Nr. 939, topic code 04, 070)