1. C. Hull, "Apparatus for production of three-dimensional objects by stereolithography," US Pat 4575330, 1984.
2. S. Crump, "Apparatus and method for creating three-dimensional objects," US Patent 5,121,329, 1989.
3. E. Sachs, J. Haggerty, M. Cima, and P. Williams, "Three-dimensional printing techniques," United States Patent 5,204,055, 1993.
4. E. Sachs, "Three-Dimensional Printing: Rapid Tooling and Prototypes Directly from a CAD Model," CIRP Ann. - Manuf. Technol., vol. 39, no. 1, pp. 201-204, 1990.
5. M. J. Cima and E. M. Sachs, "Three Dimensional Printing: Form, Materials and Performance," in Proceedings of the Solid Free For Fabrication Symposium, Austin, Texas, 1991, pp. 187-194.