Bach, F. and Jordan, M. (2002). Kernel independent component analysis,
Journal of Machine Learning Research 3: 1-48
Hastie, T. and Tibshirani, R. (2003) Independent Component Analysis
through Product Density Estimation in Advances in Neural Information
Processing Systems 15 (Becker, S. and Obermayer, K., eds), MIT Press,
Cambridge, MA. pp 649-656
Hastie, T., Tibshirani, R. and Friedman, J. (2009) Elements of
Statistical Learning (2nd edition), Springer.
https://hastie.su.domains/ElemStatLearn/printings/ESLII_print12_toc.pdf