1. A new look at scrap management;Bird;Journal of Purchasing and Materials Management,1977
2. Measuring purchasing effectiveness;Croell;Journal of Purchasing and Materials Management,1977
3. Building theories from case study research;Eisenhardt;Academy of Management Review,1989
4. Fearon, H. E. and Leenders, M. R. (1995) Purchasing’s Organizational Roles and Responsibilities. Center for Advanced Purchasing Studies, Tempe, AZ.
5. Glaser, B. G. and Strauss, A. L. (1967) The Discovery of Grounded Theory. Aldine, Chicago, IL.