<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (February 2011) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (February 2011) (Learn how and when to remove this template message) </Td> </Tr> <P> The service--profit chain is the central concept in a theory of business management which links employee satisfaction to customer loyalty and profitability . It was proposed in an article in the Harvard Business Review in 1994 by James L. Heskett, Thomas Jones, Gary Loveman, W. Earl Sasser, and Leonard Schlesinger, and was later the subject of the book The Service Profit Chain--How Leading Companies Link Profit and Growth To Loyalty, Satisfaction and Value, published in 1997 by three of the same authors . </P>

Who came up with the service profit chain
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