Travis, W. P. (1964). Theory of trade and proterction. Harvard Univ. pre.
Tohutoru Kātū Chicago (17th ed.)Travis, William Penfield. Theory of Trade and Proterction. Cambridge: Harvard Univ. pre, 1964.
Tohutoro MLA (9th ed.)Travis, William Penfield. Theory of Trade and Proterction. Harvard Univ. pre, 1964.
Kia tūpato: Kāore pea ēnei kupu hautoa i te ōrite pū 100%.