Allen, C., Kania, D., & Yaeckel, B. (2001). One-to-one Web marketing: : build a relationship marketing strategy one customer at a time (2nd edition.). Wiley.

Allen, Cliff, Deborah Kania, and Beth Yaeckel. One-to-one Web Marketing: : Build a Relationship Marketing Strategy One Customer at a Time. 2nd edition. New York: Wiley, 2001.

Allen, Cliff, et al. One-to-one Web Marketing: : Build a Relationship Marketing Strategy One Customer at a Time. 2nd edition. Wiley, 2001.