To cite package ‘LEA’ in publications use:

  Frichot E, Francois O (2015). “LEA: an R package for Landscape and
  Ecological Association studies.” _Methods in Ecology and Evolution_.
  <http://membres-timc.imag.fr/Olivier.Francois/lea.html>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {{LEA}: an {R} package for {L}andscape and {E}cological 
    {A}ssociation studies},
    author = {Eric Frichot and Olivier Francois},
    year = {2015},
    journal = {Methods in Ecology and Evolution},
    url = {http://membres-timc.imag.fr/Olivier.Francois/lea.html},
  }