Wilson, C. (1999). Profitable customers (2nd.). Kogan Page.
Lua i Stíl Chicago (17ú heag.)Wilson, Charles. Profitable Customers. 2nd. New Delhi: Kogan Page, 1999.
Lua MLA (9ú heag.)Wilson, Charles. Profitable Customers. 2nd. Kogan Page, 1999.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.