APA

Nichols D. A., Reynolds C. W., . (1971). Principles of economics. New York: Holt, Rinehart and Winston.

Chicago

Nichols Donald A, Reynolds Clark Winton, . 1971. Principles of economics. New York: Holt, Rinehart and Winston.

Harvard

Nichols D. A., Reynolds C. W., . (1971). Principles of economics. New York: Holt, Rinehart and Winston.

MLA

Nichols Donald A, Reynolds Clark Winton, . Principles of economics. New York: Holt, Rinehart and Winston. 1971.