1. Nonlinear System Identification
2. Rational model identification using an extended least-squares algorithm
3. Billings, S.A. & Zhu, Q.M. 1994. Nonlinear model validation using correlation tests.International Journal of Control,60(6), 1107–1120.
4. Billings, S.A. & Zhu, Q.M. 1995. Model validation tests for multivariable nonlinear models including neural networks.International Journal of Control,62(4), 749–766.
5. Recursive Identification and Parameter Estimation