J. Krogstie. Organizational Semiotics: Evolving a Science of Information Systems, IFIP TC8 / WG8.1 Working Conference on Organizational Semiotics: Evolving a Science of Information Systems, page 231-249. Montreal, (July 2001)
B. Boehm, J. Brown, and M. Lipow. International Conference on Software Engineering, page 592--605. San Francisco, IEEE Computer Society Press, (1976)Later published as ``Characteristics of Software Quality'', TRW series on technology, North-Holland, 1978.