Não informado. (1970). Extension news. Virginia Polytechnic Institute and State University.
Chicago-referens (17:e uppl.)Não informado. Extension News. Blacksburg, Va: Virginia Polytechnic Institute and State University, 1970.
MLA-referens (8:e uppl.)Não informado. Extension News. Virginia Polytechnic Institute and State University, 1970.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.