APA-viite (7. p.)

Spencer, H. (1891). The Principles of Ethics (2nd thousand.). Williams and Norgate.

Chicago-viite (17. p.)

Spencer, Herbert. The Principles of Ethics. 2nd thousand. London ; Edinburgh: Williams and Norgate, 1891.

MLA-viite (8. p.)

Spencer, Herbert. The Principles of Ethics. 2nd thousand. Williams and Norgate, 1891.