Barbosa-Saucedo, É. A., Gracia-Villar, S., & Dzul-López, L. A. (2011). How to improve business competitiveness in Tamaulipas?: Six Sigma, an alternative for small and medium enterprises. Universidad Autónoma de Tamaulipas.
Chicago-viite (17. p.)Barbosa-Saucedo, Édgar Alejandro, Santos Gracia-Villar, ja Luis Alonso Dzul-López. How to Improve Business Competitiveness in Tamaulipas?: Six Sigma, an Alternative for Small and Medium Enterprises. Universidad Autónoma de Tamaulipas, 2011.
MLA-viite (8. p.)Barbosa-Saucedo, Édgar Alejandro, et al. How to Improve Business Competitiveness in Tamaulipas?: Six Sigma, an Alternative for Small and Medium Enterprises. Universidad Autónoma de Tamaulipas, 2011.
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