1. Asimow, M. 1962. An Introduction to Design. Englewood Cliffs, NJ: Prentice-Hall.
2. Mantyla, M. 1988. An Introduction to Solid Modelling. Rockville, MD: Computer Science Press.
3. Zeid, I. 1991. CAD/CAM Theory and Practice. New York: McGraw-Hill.
4. Shah, J. J. and Mantyla, M. 1995. Parametric and Feature-Based CAD/CAM. New York: Wiley.
5. Chandrasekaran, B. 1994. Functional representation: a brief historical perspective. Applied Artificial Intelligence, 8 (2), pp. 173–197.