"The author describes the use of the epidiascope for showing letters, words and sounds on a screen — In his view it is the best method of educating adults in Africa, since it can be used in a darkened room, which lends courage to timid students, and because it gives the teacher more opportunity for contact with his audience." (Jean-Marie Van Bol, Abdelfattah Fakhfakh: The use of mass media in the developing countries. Brussels: CIDESA, 1971 Nr. 2272, topic code 521.2)