Martins, Yu. X., and R. J. Biezuner. “Geometric Regularity Results on $B_{\alpha,\beta}^{k}$-Manifolds, I: Affine Connections”. Methods of Functional Analysis and Topology 27, no. 3 (September 25, 2021): 237–257. Accessed December 15, 2025. https://zen.imath.kiev.ua/index.php/mfat/article/view/800.