APA (7th ed.) Citation

Roscher, W., & Lalor, J. J. (2012). Principles of Political Economy, Vol. II. Project Gutenberg.

Chicago Style (17th ed.) Citation

Roscher, Wilhelm, and John J. Lalor. Principles of Political Economy, Vol. II. Project Gutenberg, 2012.

MLA (9th ed.) Citation

Roscher, Wilhelm, and John J. Lalor. Principles of Political Economy, Vol. II. Project Gutenberg, 2012.

Warning: These citations may not always be 100% accurate.