To cite package ‘affinity’ in publications use:

Sumner M (2021). affinity: Raster Georeferencing, Grid Affine Transforms, Cell Abstraction. R package version 0.2.5, https://github.com/hypertidy/affinity.

Corresponding BibTeX entry:

  @Manual{,
    title = {affinity: Raster Georeferencing, Grid Affine Transforms,
      Cell Abstraction},
    author = {Michael D. Sumner},
    year = {2021},
    note = {R package version 0.2.5},
    url = {https://github.com/hypertidy/affinity},
  }