To cite 'forestinventory' in publications use:

Andreas Hill, Alexander Massey, Daniel Mandallaz (2017). forestinventory: Design-based global and small-area estimations for multiphase forest inventories. R package version 0.2.0

Corresponding BibTeX entry:

  @Manual{,
    title = {forestinventory: Design-based global and small-area
      estimations for multiphase forest inventories. R package version
      0.2.0},
    author = {Andreas Hill and Alexander Massey and Daniel Mandallaz},
    year = {2017},
  }