To cite package ‘leafpm’ in publications use:

  Russell K, Appelhans T (2019). _leafpm: Leaflet Map Plugin for
  Drawing and Editing_. R package version 0.1.0,
  <https://github.com/r-spatial/leafpm>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {leafpm: Leaflet Map Plugin for Drawing and Editing},
    author = {Kenton Russell and Tim Appelhans},
    year = {2019},
    note = {R package version 0.1.0},
    url = {https://github.com/r-spatial/leafpm},
  }