APA (7e ed.) Bronvermelding

RUFFIN, R. J., & GREGORY, P. R. (1988). Principles of microeconomics.-- Ed.3. Scott.

Chicago (17e ed.) Bronvermelding

RUFFIN, Roy J., en Paul R. GREGORY. Principles of Microeconomics.-- Ed.3. Boston: Scott, 1988.

MLA (9e ed.) Bronvermelding

RUFFIN, Roy J., en Paul R. GREGORY. Principles of Microeconomics.-- Ed.3. Scott, 1988.