To cite Qest in publications use:

  Sottile G, Frumento P (2022). “Robust estimation and regression with
  parametric quantile functions.” _Computational Statistics and Data
  Analysis_, *171*, 107471. doi:10.1016/j.csda.2022.107471
  <https://doi.org/10.1016/j.csda.2022.107471>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Robust estimation and regression with parametric quantile functions},
    author = {Gianluca Sottile and Paolo Frumento},
    journal = {Computational Statistics and Data Analysis},
    year = {2022},
    volume = {171},
    pages = {107471},
    doi = {10.1016/j.csda.2022.107471},
  }