APA

Spencer E. W., . (1977). Introduction to the structure of the earth. New York: McGraw Hill.

Chicago

Spencer Edgar W, . 1977. Introduction to the structure of the earth. New York: McGraw Hill.

Harvard

Spencer E. W., . (1977). Introduction to the structure of the earth. New York: McGraw Hill.

MLA

Spencer Edgar W, . Introduction to the structure of the earth. New York: McGraw Hill. 1977.