APA

Usher G., . (1974). A dictionary of plants used by man. New York: Hafner Press.

Chicago

Usher George, . 1974. A dictionary of plants used by man. New York: Hafner Press.

Harvard

Usher G., . (1974). A dictionary of plants used by man. New York: Hafner Press.

MLA

Usher George, . A dictionary of plants used by man. New York: Hafner Press. 1974.