To cite subtee in publications use:

Ballarini NM, Thomas M, Rosenkranz GK, Bornkamp B (2021). “subtee: An R Package for Subgroup Treatment Effect Estimation in Clinical Trials.” Journal of Statistical Software, 99(14), 1–17. doi: 10.18637/jss.v099.i14.

Corresponding BibTeX entry:

  @Article{,
    title = {{subtee}: An {R} Package for Subgroup Treatment Effect
      Estimation in Clinical Trials},
    author = {Nicolas M. Ballarini and Marius Thomas and Gerd K.
      Rosenkranz and Bj{\"o}rn Bornkamp},
    journal = {Journal of Statistical Software},
    year = {2021},
    volume = {99},
    number = {14},
    pages = {1--17},
    doi = {10.18637/jss.v099.i14},
  }