Cleff, Thomas. “Using International Trade Data for Evaluating the Product Specific Competitiveness and Supplied Product Quality of Countries: A Successful Example of Applied Theory”. Gadjah Mada International Journal of Business 8, no. 2 (May 12, 2006): 229 - 246. Accessed November 23, 2024. https://jurnal.ugm.ac.id/v3/gamaijb/article/view/14877.