6PRAHALAD,HAMEL. The core competence of the eorpo ration[J], Harvard Business Review,1990(3):79-91.
7BARTON. Core capabilities and core rigidities: A paradox in management new product development[J]. Strategic Man agement Journal, 1992 (13) : 111-125.
8BARNEY. Firm resources and sustained competitive advantage[J]. Journal of Management, 1991 (17) :99-120.