APA-viite (7. p.)

Gibson, W. R. B. (1904). A philosophical introduction to ethics: An advocacy of the spiritual principle in ethics from the point of view of personal idealism. S. Sonnenschein & Co., lim..

Chicago-viite (17. p.)

Gibson, William Ralph Boyce. A Philosophical Introduction to Ethics: An Advocacy of the Spiritual Principle in Ethics from the Point of View of Personal Idealism. London: S. Sonnenschein & Co., lim., 1904.

MLA-viite (8. p.)

Gibson, William Ralph Boyce. A Philosophical Introduction to Ethics: An Advocacy of the Spiritual Principle in Ethics from the Point of View of Personal Idealism. S. Sonnenschein & Co., lim., 1904.