Harvard Business Review. (2011). Harvard Business Review on Increasing Customer Loyalty. Harvard Business School.
Lua i Stíl Chicago (17ú heag.)Harvard Business Review. Harvard Business Review on Increasing Customer Loyalty. Boston: Harvard Business School, 2011.
Lua MLA (9ú heag.)Harvard Business Review. Harvard Business Review on Increasing Customer Loyalty. Harvard Business School, 2011.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.