APA

Wardhaugh R., . (19711972). Introduction to linguistics. New York: McGraw-Hill.

Chicago

Wardhaugh Ronald, . 19711972. Introduction to linguistics. New York: McGraw-Hill.

Harvard

Wardhaugh R., . (19711972). Introduction to linguistics. New York: McGraw-Hill.

MLA

Wardhaugh Ronald, . Introduction to linguistics. New York: McGraw-Hill. 19711972.