Dillon, W., Firtle, N. H., & Madden, T. J. (1993). Essentials of marketing research. McGraw-Hill.

Dillon, William, Neil H. Firtle, and Thomas J. Madden. Essentials of Marketing Research. Boston: McGraw-Hill, 1993.

Dillon, William, et al. Essentials of Marketing Research. McGraw-Hill, 1993.