Παραπομπή APA

Lipsey, R. G. (1974). An introduction to positive economics. English Language Book Society.

Παραπομπή Chicago Style

Lipsey, Richard G. An Introduction to Positive Economics. Britain: English Language Book Society, 1974.

Παραπομπή MLA

Lipsey, Richard G. An Introduction to Positive Economics. English Language Book Society, 1974.