APA (7th ed.) Citation

Nys, E., Dryhurst, N. F., & Dryhurst, A. R. (1899). Researches in the history of economics. A. & C. Black.

Chicago Style (17th ed.) Citation

Nys, Ernest, N. F. Dryhurst, and Alfred Robert Dryhurst. Researches in the History of Economics. London: A. & C. Black, 1899.

MLA (9th ed.) Citation

Nys, Ernest, et al. Researches in the History of Economics. A. & C. Black, 1899.