APA استشهاد

Johnson, H. G. (1971). Aspects of the Theory of Tariffs. Allen & Unwin.

استشهاد بنمط شيكاغو

Johnson, Harry G. Aspects of the Theory of Tariffs. London: Allen & Unwin, 1971.

MLA استشهاد

Johnson, Harry G. Aspects of the Theory of Tariffs. Allen & Unwin, 1971.