Cita APA (7a ed.)

Gemmill, P. F. (1948). Economics: Principles and problems (3rd ed. vol. 1 & 2.). Harper.

Cita Chicago Style (17a ed.)

Gemmill, Paul F. Economics: Principles and Problems. 3rd ed. vol. 1 & 2. New York: Harper, 1948.

Cita MLA (9a ed.)

Gemmill, Paul F. Economics: Principles and Problems. 3rd ed. vol. 1 & 2. Harper, 1948.