Não informado. (1991). Adult Basic Education. Commission on Adult Basic Education.
Chicago-referens (17:e uppl.)Não informado. Adult Basic Education. Atlanta, Ga: Commission on Adult Basic Education, 1991.
MLA-referens (8:e uppl.)Não informado. Adult Basic Education. Commission on Adult Basic Education, 1991.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.