APA

Skinner B. F., . (1972). Walden Two. New York: Macmillan.

Chicago

Skinner B F, . 1972. Walden Two. New York: Macmillan.

Harvard

Skinner B. F., . (1972). Walden Two. New York: Macmillan.

MLA

Skinner B F, . Walden Two. New York: Macmillan. 1972.