Cita APA (7th ed.)

Wallis, W. A., & Roberts, H. V. (1956). Statistics a new approach. The Free.

Cita Chicago (17th ed.)

Wallis, W. Allen, i Harry V. Roberts. Statistics a New Approach. Nueva York: The Free, 1956.

Cita MLA (9th ed.)

Wallis, W. Allen, i Harry V. Roberts. Statistics a New Approach. The Free, 1956.