Cita APA (7th ed.)

Koch, A. R. (1986). Economic principles: Growth and environment. Avi.

Cita Chicago (17th ed.)

Koch, A. Robert. Economic Principles: Growth and Environment. Westport, Conn.: Avi, 1986.

Cita MLA (9th ed.)

Koch, A. Robert. Economic Principles: Growth and Environment. Avi, 1986.