Cita APA (7a ed.)

Elderton, W. P., & Johnson, N. L. (1969). Systems of frequency curves. Cambridge University.

Cita Chicago Style (17a ed.)

Elderton, William Palin, y Norman Lloyd Johnson. Systems of Frequency Curves. Cambridge: Cambridge University, 1969.

Cita MLA (9a ed.)

Elderton, William Palin, y Norman Lloyd Johnson. Systems of Frequency Curves. Cambridge University, 1969.