To cite package ‘gsynth’ in publications use:

  Xu Y, Liu L, Liu Z, Hu S (2026). _gsynth: Generalized Synthetic
  Control Method_. R package version 1.4.0,
  <https://github.com/xuyiqing/gsynth>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {gsynth: Generalized Synthetic Control Method},
    author = {Yiqing Xu and Licheng Liu and Ziyi Liu and Shiyun Hu},
    year = {2026},
    note = {R package version 1.4.0},
    url = {https://github.com/xuyiqing/gsynth},
  }