APA

Gilbert E. W., . (1966). The exploration of western America, 1800-1850: an historical geography. New York: Cooper Square Publishers.

Chicago

Gilbert Edmund William, . 1966. The exploration of western America, 1800-1850: an historical geography. New York: Cooper Square Publishers.

Harvard

Gilbert E. W., . (1966). The exploration of western America, 1800-1850: an historical geography. New York: Cooper Square Publishers.

MLA

Gilbert Edmund William, . The exploration of western America, 1800-1850: an historical geography. New York: Cooper Square Publishers. 1966.