Pande, P. S., & Holpp, L. (2002). What is six sigma? McGraw-Hill ; Tata McGraw Hill.

Pande, Peter S., and Lawrence Holpp. What Is Six Sigma? New York : New Delhi: McGraw-Hill ; Tata McGraw Hill, 2002.

Pande, Peter S., and Lawrence Holpp. What Is Six Sigma? McGraw-Hill ; Tata McGraw Hill, 2002.