@article{6:32,author={Aharon Bar-Hillel and Tomer Hertz and Noam Shental and Daphna Weinshall}, Title={Learning a Mahalanobis Metric from Equivalence Constraints},journal={Journal of Machine Learning Research},volume={6}, url={http://www.jmlr.org/papers/volume6/bar-hillel05a/bar-hillel05a.pdf}}