Cita APA (7th ed.)

Weizsacker, E. v., Lovins, A. B., & Lovins, L. H. (1997). Factor four: Doubling wealth, halving resource use. Earthscan.

Cita Chicago (17th ed.)

Weizsacker, Ernst von, Amory B. Lovins, i L. Hunter Lovins. Factor Four: Doubling Wealth, Halving Resource Use. London: Earthscan, 1997.

Cita MLA (9th ed.)

Weizsacker, Ernst von, et al. Factor Four: Doubling Wealth, Halving Resource Use. Earthscan, 1997.