APA

Langer W. L., Gleason S. E., . (19701952). The challenge to isolation: the world crisis of 1937-1940 and American foreign policy. Gloucester, Mass: Peter Smith.

Chicago

Langer William L, Gleason Sarell Everett, . 19701952. The challenge to isolation: the world crisis of 1937-1940 and American foreign policy. Gloucester, Mass: Peter Smith.

Harvard

Langer W. L., Gleason S. E., . (19701952). The challenge to isolation: the world crisis of 1937-1940 and American foreign policy. Gloucester, Mass: Peter Smith.

MLA

Langer William L, Gleason Sarell Everett, . The challenge to isolation: the world crisis of 1937-1940 and American foreign policy. Gloucester, Mass: Peter Smith. 19701952.