To cite package ‘RCSF’ in publications use:

  Roussel J, Qi J (2020). _RCSF: Airborne LiDAR Filtering Method Based
  on Cloth Simulation_. R package version 1.0.2,
  <https://github.com/r-lidar/rcsf>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {RCSF: Airborne LiDAR Filtering Method Based on Cloth Simulation},
    author = {Jean-Romain Roussel and Jianbo Qi},
    year = {2020},
    note = {R package version 1.0.2},
    url = {https://github.com/r-lidar/rcsf},
  }