Παραπομπή σε μορφή APA (7η εκδ.)

Reichheld, F. F. (2006). The ultimate question: Driving good profits and true growth (NA.). Harvard Business School Press.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Reichheld, Frederick F. The Ultimate Question: Driving Good Profits and True Growth. NA. USA: Harvard Business School Press, 2006.

Παραπομπή σε μορφή MLA (9th εκδ.)

Reichheld, Frederick F. The Ultimate Question: Driving Good Profits and True Growth. NA. Harvard Business School Press, 2006.