APA (7th ed.) Citation

Valk, W. L. (1928). The principles of wages. P.S. King & son, ltd..

Chicago Style (17th ed.) Citation

Valk, Willem Lodewijk. The Principles of Wages. London: P.S. King & son, ltd., 1928.

MLA (9th ed.) Citation

Valk, Willem Lodewijk. The Principles of Wages. P.S. King & son, ltd., 1928.