@article{JMLR:v24:22-1153,
  author  = {Toni Karvonen and Chris J. Oates},
  title   = {Maximum likelihood estimation in Gaussian process regression is ill-posed},
  journal = {Journal of Machine Learning Research},
  year    = {2023},
  volume  = {24},
  number  = {120},
  pages   = {1--47},
  url     = {http://jmlr.org/papers/v24/22-1153.html}
}