To cite SPOT in publications use:

Bartz-Beielstein T, Zaefferer M, Rehbach F (2021). “In a Nutshell – The Sequential Parameter Optimization Toolbox.” arXiv e-prints, arXiv:1712.04076. https://arxiv.org/abs/1712.04076.

Corresponding BibTeX entry:

  @Article{,
    title = {In a Nutshell -- The Sequential Parameter Optimization
      Toolbox},
    author = {Thomas Bartz-Beielstein and Martin Zaefferer and Frederik
      Rehbach},
    year = {2021},
    journal = {arXiv e-prints},
    pages = {arXiv:1712.04076},
    url = {https://arxiv.org/abs/1712.04076},
  }