(1985) “AMA Board approves new marketing definition,” Marketing News, March 1. Brennecke, S. (1998). Voorlichting over marktonderzoek blijft nodig [In Dutch: The necessity of correct information on market research]. Memorandum "Uw Mening Telt", April 1998. Dillman, D.A., Gallegos, J.G., & Frey, J.H. (1976). Reducing refusal rates for telephone interviews. Public Opinion Quarterly, 40, 66-78. Gronroos, C. (1994) From marketing mix to relationship marketing: towards a paradigm shift in marketing. Management Decision, 32, 2, 4-20. Groves, R.M., & Couper, M.P. (1998). Nonresponse in household interview surveys. New York, Wiley. Heberlein, T.A., & Baumgartner, R.M. (1978). Factors affecting response rates to mailed questionnaires: A quantitative analysis of the published literature. American Sociological Review, 43, 447-462. IMPEL2 project – IMpact on People of Electronic Libraries. http://ilm.ac.uk/impel Kotler, P. (1994) Marketing management: analysis, planning, implementation and control. 8th ed. London, Prentice-Hall. Leeuwen, R. van and Leeuw, E.D. de (1999). I am not selling anything: experiments in telephone introductions International Conference on Survey Nonresponse, http://www.jpsm.umd.edu/icsn/papers/Deleeuw.htm Lynn, P., Turner, R., Smith, P. (1997). The effect of complexity and tone of an advance letter on response to an interview survey. Survey Methods Centre Newsletter, 17, 13-17. Peters, T. (1995) The pursuit of Wow! Every person’s guide to topsy-turvy times. Basingstoke, Macmillan. Webber, S. Marketing library and information services. February 2000 http://www.dis.strath.ac.uk/people/sheila/marketing Yin, R.K. (1988) Case study research: design and methods. Rev.ed. London, Sage.