См.: Jonathan L. Freedman and Scott C. Fraser (1966), Compliance Without Pressure: The Foot-in-the-Door Technique, Journal of Personality and Social Psychology, 4, 195–203. См. также: Robert Cialdini (2000), Influence: Science and Practice, 4th ed., New York: Allyn & Bacon, ch. 3; Freedman and Fraser, Compliance Without Pressure, p. 201.