https://pdfs.semanticscholar.org/91ca/5fd33d2eb7c7b87f96ae59...
by Dr. David Canfield Smith, Charles Irby, Ralph Kimball, and Bill Verplank; Xerox Corporation, 3333 Coyote Hill Rd., Palo Alto, CA 94304 and Eric Harslem; Xerox Corporation, El Segundo, CA 90245
About the Authors
These five Xerox employees have worked on the Star user interface project for the past five years. Their academic backgrounds are in computer science and psychology.
"We have learned from Star the importance of formulating the fundamental concepts (the user’s conceptual model) before software is written, rather than tacking on a user interface afterward. Xerox devoted about thirty work-years to the design of the Star user interface. It was designed before the functionality of the system was fully decided. It was even designed before the computer hardware was built. In fact, before we even began designing the model, we developed a methodology by which we would do the design."