Gaya APA

Ricardo, D., Swanson, C, P. (NULL). The Principles of Political Economy and Taxation . London:: London: J.M. Dent & Sons; 1949.

Gaya MLA

Ricardo, David., Swanson, Carl, P.. "The Principles of Political Economy and Taxation". London:: London: J.M. Dent & Sons; 1949, NULL. Text.