1. John Humble and Management Centre Europe, Service: the new competitive edge.
2. Michael Quinn and John Humble, Service: the new competitive edge, a survey of executive opinion of senior managers in Ireland; Sponsored by Digital Equipment and carried out by Digital and the Marketing Institute.
3. Nine lessons on service quality;Gummesson;the TQM magazine,1989
4. Prescriptions for a service quality revolution in America;Berry;Organizational Dynamics,1992
5. The Marketing Imagination;Levitt,1986