Team, Support. “Which Robust Versions of Sample Variance and Sample Covariance Are Most Appropriate for Econometrics: Symmetry-Based Analysis: Songsak Sriboonchitta, Ildar Batyrshin, Vladik Kreinovich”. Thai Journal of Mathematics (October 28, 2016): 37–50. Accessed December 22, 2024. https://thaijmath2.in.cmu.ac.th/index.php/thaijmath/article/view/562.