T. Ezzat, G. Geiger, und T. Poggio. Proceedings of the 29th Annual Conference on Computer Graphics and Interactive Techniques (SIGGRAPH), Seite 388-398. San Antonio, TX, USA, (Juli 2002)
A. Hunt, und A. Black. Proceedings of the 1996 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 1, Seite 373-376. Atlanta, GA, USA, (Mai 1996)