APA-referens (7:e uppl.)

Não informado. (1958). Lead Abstracts. Lead Development Association.

Chicago-referens (17:e uppl.)

Não informado. Lead Abstracts. London: Lead Development Association, 1958.

MLA-referens (8:e uppl.)

Não informado. Lead Abstracts. Lead Development Association, 1958.

Varning: dessa hänvisningar är inte alltid fullständigt riktiga.