To cite package ‘gsDesign2’ in publications use:

Anderson K, Zhao Y, Zhang Y, Blischak J, Xie Y, Xiao N, Yang J (2026). gsDesign2: Group Sequential Design with Non-Constant Effect. R package version 1.1.8, https://github.com/merck/gsdesign2.

Corresponding BibTeX entry:

  @Manual{,
    title = {gsDesign2: Group Sequential Design with Non-Constant
      Effect},
    author = {Keaven Anderson and Yujie Zhao and Yilong Zhang and John
      Blischak and Yihui Xie and Nan Xiao and Jianxiao Yang},
    year = {2026},
    note = {R package version 1.1.8},
    url = {https://github.com/merck/gsdesign2},
  }