To cite mexhaz in publications use:

  Charvat H, Belot A (2021). “mexhaz: An R Package for Fitting Flexible
  Hazard-Based Regression Models for Overall and Excess Mortality with
  a Random Effect.” _Journal of Statistical Software_, *98*(14), 1-36.
  doi:10.18637/jss.v098.i14 <https://doi.org/10.18637/jss.v098.i14>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {{mexhaz}: An {R} Package for Fitting Flexible Hazard-Based Regression Models for Overall and Excess Mortality with a Random Effect},
    author = {Hadrien Charvat and Aur\'elien Belot},
    journal = {Journal of Statistical Software},
    year = {2021},
    volume = {98},
    number = {14},
    pages = {1--36},
    doi = {10.18637/jss.v098.i14},
  }