Παραπομπή APA

Peterson, W. L. (1986). Principles of ecconomics. Universal Book Stall.

Παραπομπή Chicago Style

Peterson, Willis L. Principles of Ecconomics. New Delhi: Universal Book Stall, 1986.

Παραπομπή MLA

Peterson, Willis L. Principles of Ecconomics. Universal Book Stall, 1986.