To cite the package 'isopam' in publications use:

  Schmidtlein S, Tichy L, Hannes F, Ulrike F (2010). “A brute force
  approach to vegetation classification.” _Journal of Vegetation
  Science_, *21*(6), 1162-1171.

A BibTeX entry for LaTeX users is

  @Article{,
    author = {Sebastian Schmidtlein and Lubomir Tichy and Feilhauer Hannes and Faude Ulrike},
    year = {2010},
    title = {A brute force approach to vegetation classification},
    journal = {Journal of Vegetation Science},
    volume = {21},
    number = {6},
    pages = {1162-1171},
  }