To cite gptoolsStan in publications use:

Hoffmann T, Onnela J (2025). “gptools: Scalable Gaussian Process Inference with Stan.” Journal of Statistical Software, 112(2), 1–31. doi:10.18637/jss.v112.i02.

Corresponding BibTeX entry:

  @Article{,
    title = {{gptools}: Scalable {G}aussian Process Inference with
      {Stan}},
    author = {Till Hoffmann and Jukka-Pekka Onnela},
    journal = {Journal of Statistical Software},
    year = {2025},
    volume = {112},
    number = {2},
    pages = {1--31},
    doi = {10.18637/jss.v112.i02},
  }