Time series prediction using support vector machines, the orthogonal and the regularized orthogonal least-squares algorithms. - Kian L. Lee; Stephen A. Billings (Int. J. Syst. Sci., 2002)

Nonlinear Fisher discriminant analysis using a minimum squared error cost function and the orthogonal least squares algorithm. - Stephen A. Billings; Kian L. Lee (Neural Networks, 2002)

A Smoothing Algorithm for Nonlinear Time Series. - Stephen A. Billings; Kian L. Lee (Int. J. Bifurc. Chaos, 2004)