Spanish testament.

MLA

Koestler, Arthur, and Katharine Atholl. Spanish Testament. London: Gollancz, 1937.

APA

Koestler, A., & Atholl, K. (1937). Spanish testament. London: Gollancz.

Chicago

Koestler, Arthur, and Katharine Atholl. Spanish Testament. London: Gollancz, 1937.