To cite package ‘heckmanGE’ in publications use:

  Fernando de Souza B, Rogério Jerônimo B, Marcos Oliveira P (2024).
  _heckmanGE: Estimation and Inference for Heckman Selection Models
  with Cluster-Robust Variance_. R package version 1.0.0,
  <https://CRAN.R-project.org/package=heckmanGE>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {heckmanGE: Estimation and Inference for Heckman Selection Models with
Cluster-Robust Variance},
    author = {Bastos {Fernando de Souza} and Barbosa {Rogério Jerônimo} and Prates {Marcos Oliveira}},
    year = {2024},
    note = {R package version 1.0.0},
    url = {https://CRAN.R-project.org/package=heckmanGE},
  }