To cite package ‘slippymath’ in publications use:

McBain M, Sumner M (2019). slippymath: Slippy Map Tile Tools. R package version 0.3.1, https://github.com/milesmcbain/slippymath.

Corresponding BibTeX entry:

  @Manual{,
    title = {slippymath: Slippy Map Tile Tools},
    author = {Miles McBain and Michael Sumner},
    year = {2019},
    note = {R package version 0.3.1},
    url = {https://github.com/milesmcbain/slippymath},
  }