Não informado. (1956). Educational Screen and Audio-visual Guide. Educational Screen.
Chicago-referens (17:e uppl.)Não informado. Educational Screen and Audio-visual Guide. Chicago, Ill: Educational Screen, 1956.
MLA-referens (8:e uppl.)Não informado. Educational Screen and Audio-visual Guide. Educational Screen, 1956.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.