Zemke, R. (1990). The Service edge: 101 companies that profit from customer care. Penguin Books USA Inc.
Chicago Style (17th ed.) CitationZemke, Ron. The Service Edge: 101 Companies That Profit from Customer Care. New York: Penguin Books USA Inc, 1990.
MLA (8th ed.) CitationZemke, Ron. The Service Edge: 101 Companies That Profit from Customer Care. Penguin Books USA Inc, 1990.
Warning: These citations may not always be 100% accurate.