Sinclair, U., & Downs, R. B. (1960). The jungle: Upton Sinclair. With an afterw. by Robert B. Downs (20. print.). New American Library.
Citazione stile Chigago Style (17a edizione)Sinclair, Upton, e Robert B. Downs. The Jungle: Upton Sinclair. With an Afterw. by Robert B. Downs. 20. print. New York: New American Library, 1960.
Citatione MLA (8a ed.)Sinclair, Upton, e Robert B. Downs. The Jungle: Upton Sinclair. With an Afterw. by Robert B. Downs. 20. print. New American Library, 1960.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.