Cita APA (7a ed.)

Spencer, H. (1891). Essays: Scientific, political, & speculative (Library ed., containing seven essays not before republished, and various other additions.). Williams and Norgate.

Cita Chicago Style (17a ed.)

Spencer, Herbert. Essays: Scientific, Political, & Speculative. Library ed., containing seven essays not before republished, and various other additions. London ; Edinburgh: Williams and Norgate, 1891.

Cita MLA (9a ed.)

Spencer, Herbert. Essays: Scientific, Political, & Speculative. Library ed., containing seven essays not before republished, and various other additions. Williams and Norgate, 1891.