APA

Wardhaugh R., . (1977). Introduction to linguistics. New York: McGraw-Hill Book Company.

Chicago

Wardhaugh Ronald, . 1977. Introduction to linguistics. New York: McGraw-Hill Book Company.

Harvard

Wardhaugh R., . (1977). Introduction to linguistics. New York: McGraw-Hill Book Company.

MLA

Wardhaugh Ronald, . Introduction to linguistics. New York: McGraw-Hill Book Company. 1977.