Wawrzyniak, J., K. Jąder, G. Schade, and D. Leitow. “Consumers? Attitudes and Behaviour in Relation to Regional Products - Results of Empirical Research in Germany and Poland”. Journal of Agribusiness and Rural Development, Vol. 4, no. 359, Dec. 2005, pp. 145-56, http://www1.up.poznan.pl/jard/index.php/jard/article/view/1009.