To cite package ‘nna’ in publications use:

Pereira C, Castro C (2018). nna: Nearest-Neighbor Analysis. R package version 0.0.2.1, https://CRAN.R-project.org/package=nna.

Corresponding BibTeX entry:

  @Manual{,
    title = {nna: Nearest-Neighbor Analysis},
    author = {Cristiano Pereira and Clovis Castro},
    year = {2018},
    note = {R package version 0.0.2.1},
    url = {https://CRAN.R-project.org/package=nna},
  }