APA (7e ed.) Bronvermelding

Howarth, S. (1997). A century in oil: The "Shell" Transport and Trading Company 1897-1997. Weidenfeld & Nicolson.

Chicago (17e ed.) Bronvermelding

Howarth, Stephen. A Century in Oil: The "Shell" Transport and Trading Company 1897-1997. London: Weidenfeld & Nicolson, 1997.

MLA (8e ed.) Bronvermelding

Howarth, Stephen. A Century in Oil: The "Shell" Transport and Trading Company 1897-1997. Weidenfeld & Nicolson, 1997.