APA

Urmson J. O., . (19671960). The Concise encyclopedia of Western phylosophy and philosophers. New York: Hawthorn Books.

Chicago

Urmson J O, . 19671960. The Concise encyclopedia of Western phylosophy and philosophers. New York: Hawthorn Books.

Harvard

Urmson J. O., . (19671960). The Concise encyclopedia of Western phylosophy and philosophers. New York: Hawthorn Books.

MLA

Urmson J O, . The Concise encyclopedia of Western phylosophy and philosophers. New York: Hawthorn Books. 19671960.