APA-referens (7:e uppl.)

Duckworth, H. A. &. H. (2016). A Six sigma approach to sustainability. CRC Press.

Chicago-referens (17:e uppl.)

Duckworth, Holly A. & Hoffmeier. A Six Sigma Approach to Sustainability. Boca Ratan: CRC Press, 2016.

MLA-referens (9:e uppl.)

Duckworth, Holly A. & Hoffmeier. A Six Sigma Approach to Sustainability. CRC Press, 2016.