Albert Karl, & J. Bradford Lawrence. (1990). The Service Advantage: How to Identify and Fulfill Customer Needs (In lần thứ 1.). U.S.A: Dow Jones - Irwin.
استشهاد بنمط شيكاغوAlbert Karl, و J. Bradford Lawrence. The Service Advantage: How to Identify and Fulfill Customer Needs. In lần thứ 1. U.S.A: Dow Jones - Irwin, 1990.
MLA استشهادAlbert Karl, و J. Bradford Lawrence. The Service Advantage: How to Identify and Fulfill Customer Needs. In lần thứ 1. U.S.A: Dow Jones - Irwin, 1990.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.