Gaya APA

Pyzdek, T., Keller, P. (2010). The Six sigma handbook : a complete guide for green belts, black belts, and managers at all levels (3rd ed). New York: McGraw-Hill.

Gaya MLA

Pyzdek, Thomas., Keller, Paul. "The Six sigma handbook : a complete guide for green belts, black belts, and managers at all levels". 3rd ed New York: McGraw-Hill, 2010. Text.