APA

Fruehling R. T., Bouchard S., . (1972). The art of writing effective letters. New York: McGraw-Hill.

Chicago

Fruehling Rosemary T, Bouchard Sharon, . 1972. The art of writing effective letters. New York: McGraw-Hill.

Harvard

Fruehling R. T., Bouchard S., . (1972). The art of writing effective letters. New York: McGraw-Hill.

MLA

Fruehling Rosemary T, Bouchard Sharon, . The art of writing effective letters. New York: McGraw-Hill. 1972.