@article{3:59,author={Jason Weston and Andr Elisseeff and Bernhard Schlkopf and Mike Tipping}, Title={Use of the Zero-Norm with Linear Models and Kernel Methods
(Kernel Machines Section)},journal={Journal of Machine Learning Research},volume={3}, url={http://www.jmlr.org/papers/volume3/rivals03a/rivals03a.pdf}}