Não informado. (1989). Adult Learning. American Association for Adult & Continuing Education.
Chicago-referens (17:e uppl.)Não informado. Adult Learning. Washington: American Association for Adult & Continuing Education, 1989.
MLA-referens (8:e uppl.)Não informado. Adult Learning. American Association for Adult & Continuing Education, 1989.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.