To cite package ‘glmmPen’ in publications use:

  Heiling H, Rashid N, Li Q, Ibrahim J (2024). _glmmPen: High
  Dimensional Penalized Generalized Linear Mixed Models (pGLMM)_. R
  package version 1.5.4.8,
  <https://CRAN.R-project.org/package=glmmPen>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {glmmPen: High Dimensional Penalized Generalized Linear Mixed Models
(pGLMM)},
    author = {Hillary Heiling and Naim Rashid and Quefeng Li and Joseph Ibrahim},
    year = {2024},
    note = {R package version 1.5.4.8},
    url = {https://CRAN.R-project.org/package=glmmPen},
  }