@article{asimpleproofofoptimalapproximations,
  title = {Optimal Approximations Made Easy},
  author = {Mónika Csikós and Nabil H. Mustafa},
  year = {2020},
  eprint = {2008.08970},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2008.08970v3},
}