@misc{Doe2023, doi = {10.48550/ARXIV.2301.11992}, url = {https://arxiv.org/abs/2301.11992}, author = {Dölz, Jürgen}, title = {Data sparse multilevel covariance estimation in optimal complexity}, publisher = {arXiv}, year = {2023}, eprint={2301.11992}, archivePrefix={arXiv} }