@article {GillisVavasis, title = {Fast and Robust Recursive Algorithms for Separable Nonnegative Matrix Factorization}, journal = {IEEE Trans. Pattern Analysis and Machine Intelligence}, volume = {36}, year = {2013}, note = {Arxiv link: https://arxiv.org/abs/1208.1237}, pages = {698-714}, author = {N. Gillis and S. A. Vavasis} }