Citazione Stile APA (7a Edizione)

Travis, W. P. (1964). Theory of trade and proterction. Harvard Univ. pre.

Citazione stile Chigago Style (17a edizione)

Travis, William Penfield. Theory of Trade and Proterction. Cambridge: Harvard Univ. pre, 1964.

Citatione MLA (9a ed.)

Travis, William Penfield. Theory of Trade and Proterction. Harvard Univ. pre, 1964.