Não informado. (1989). Education Today. Ontario Public School Board's Association.
Chicago-referens (17:e uppl.)Não informado. Education Today. Toronto, Canada: Ontario Public School Board's Association, 1989.
MLA-referens (8:e uppl.)Não informado. Education Today. Ontario Public School Board's Association, 1989.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.