1. Bush, John, B.: “Bringing Inventors and Needs Together,” Speech to the International Association for Product Development. Peachtree City, GA, March 9–11 (1998).
2. Focus Groups and the Nature of Qualitative Marketing Research;Calder;Journal of Marketing Research,1977
3. Marketing Research Methodological Foundations;Churchill,1991
4. New Products;Cooper;Journal of Product and Innovation Management,1987
5. Applications of Focus Group Interviews in Marketing;Cox;Journal of Marketing,1976