Groupwise Statistics, LSmeans, Linear Contrasts, Utilities
Author: Søren Højsgaard, Ulrich Halekoh
CRAN page:
https://cran.r-project.org/web/packages/doBy/index.html
Further info at:
http://people.math.aau.dk/~sorenh/software/doBy/
https://github.com/hojsgaard/doBy