To cite package 'autopls' in publications use:

Schmidtlein, S, Feilhauer, H., Bruelheide, H. (2012): Mapping plant strategy types using remote sensing. Journal of Vegetation Science 26: 395-405. url = http://dx.doi.org/10.1111/j.1654-1103.2011.01370.x

Corresponding BibTeX entry:

  @Article{,
    title = {Mapping plant strategy types using remote sensing},
    author = {Sebastian Schmidtlein and Hannes Feilhauer and Helge
      Bruelheide},
    journal = {Journal of Vegetation Science},
    url = {http://dx.doi.org/10.1111/j.1654-1103.2011.01370.x},
    doi = {10.1111/j.1654-1103.2011.01370.x},
    pages = {365--405},
    year = {2012},
    volume = {23},
  }