Cita APA (7a ed.)

Spencer, H. (1890). The principles of psychology (3rd ed.). Williams and Norgate.

Cita Chicago Style (17a ed.)

Spencer, Herbert. The Principles of Psychology. 3rd ed. London: Williams and Norgate, 1890.

Cita MLA (9a ed.)

Spencer, Herbert. The Principles of Psychology. 3rd ed. Williams and Norgate, 1890.