GERSON RICHARD F. (2004). BEYOND CUSTOMER SERVICE. VIVA BOOKS PVT.LTD.
Lua i Stíl Chicago (17ú heag.)GERSON RICHARD F. BEYOND CUSTOMER SERVICE. NEW DELHI: VIVA BOOKS PVT.LTD, 2004.
Lua MLA (9ú heag.)GERSON RICHARD F. BEYOND CUSTOMER SERVICE. VIVA BOOKS PVT.LTD, 2004.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.