Pegoraro, M., and M. Beraha. “Fast PCA in 1-D Wasserstein Spaces via B-Splines Representation and Metric Projection”. Proceedings of the AAAI Conference on Artificial Intelligence, vol. 35, no. 10, May 2021, pp. 9342-9, https://ojs.aaai.org/index.php/AAAI/article/view/17126.