APA-referens (7:e uppl.)

Não informado. Transport economics. Interstate Commerce Commission, Bureau of Transport Economics and Statistics.

Chicago-referens (17:e uppl.)

Não informado. Transport Economics. Washington: Interstate Commerce Commission, Bureau of Transport Economics and Statistics.

MLA-referens (8:e uppl.)

Não informado. Transport Economics. Interstate Commerce Commission, Bureau of Transport Economics and Statistics.

Varning: dessa hänvisningar är inte alltid fullständigt riktiga.