E. Altman and N. Ahuja and F. Kishino, Hand Trajectory Recognition Using Dynamical Systems, First Asian Conference on Computer Vision, November 23-25, 1993, Osaka, Japan, 321-324. 

M.-H. Yang and N. Ahuja, Extracting Gestural Motion Trajectory, 1998 IEEE International Conference on Automatic Face and Gesture Recognition, Nara, Japan, April 1998, 10-15. 

M.-H. Yang and N. Ahuja, Extraction and Classification of Motion Patterns for Hand Gesture Recognition, IEEE Computer Society Conference on Computer Vision and Pattern Recognition, Santa Barbara, CA, June 1998, 892-897. 

M.H. Yang and N. Ahuja, Gaussian Mixture Modeling of Human Skin Color and Its Applications in Image and Video Databases, Proc. of the SPIE: Storage and Retrieval for Image and Video Databases VI, Vol. 3656, San Jose, CA, Jan. 1999, 458-466. Abstract