1. (1968a). Word of mouth advertising and perceived risk. In and (Eds.), Perspectives in consumer behavior (pp. 330–336). Glenview: Scott, Foresman & Co.
2. (1986b). Profiling consumer innovators. In (Eds.), Insights into consumer behavior (pp. 71–83). Boston: Allyn and Bacon.
3. (1974). New product diffusion: The interplay of innovativeness, opinion leadership, learning, perceived risk and product attributes. In (Ed.), Models of buyer behaviour (pp. 327–335). New York: Harper and Row.