Cita APA (7th ed.)

Thornton, A. P. (1977). Imperialism in the twentieth century. University of Minnesota Press.

Cita Chicago (17th ed.)

Thornton, A. P. Imperialism in the Twentieth Century. Minneapolis: University of Minnesota Press, 1977.

Cita MLA (9th ed.)

Thornton, A. P. Imperialism in the Twentieth Century. University of Minnesota Press, 1977.