APA (7th ed.) Citation

Empson, W. (1947). Seven types of ambiguity ([3d ed.). New Directions.

Chicago Style (17th ed.) Citation

Empson, William. Seven Types of Ambiguity. [3d ed. New York]: New Directions, 1947.

MLA (9th ed.) Citation

Empson, William. Seven Types of Ambiguity. [3d ed. New Directions, 1947.