APA

Doyle A. C., . (1930). The edge of the unknown. New York: Purnam's.

Chicago

Doyle Arthur Conan, . 1930. The edge of the unknown. New York: Purnam's.

Harvard

Doyle A. C., . (1930). The edge of the unknown. New York: Purnam's.

MLA

Doyle Arthur Conan, . The edge of the unknown. New York: Purnam's. 1930.