Cox, K. K., Enis, B. M., & Keith cox K. (1973). Readings in the marketing research process. Good Year publishsing company.

Cox, Keith K., Ben M. Enis, and Keith cox K. Readings in the Marketing Research Process. California: Good Year publishsing company, 1973.

Cox, Keith K., et al. Readings in the Marketing Research Process. Good Year publishsing company, 1973.