@misc{varma2020down,
  title={Up-down instability of binary black holes in numerical relativity},
  author={Vijay Varma and Matthew Mould and Davide Gerosa and Mark A. Scheel and Lawrence E. Kidder and Harald P. Pfeiffer},
  year={2020},
  eprint={2012.07147},
  archivePrefix={arXiv},
  primaryClass={gr-qc},
  url={https://arxiv.org/abs/2012.07147}
}