To cite mefa4 in publications use:

Peter Solymos (2009). Processing Ecological Data in R with the mefa Package. Journal of Statistical Software 29(8), 1-28. URL http://www.jstatsoft.org/v29/i08/.

Corresponding BibTeX entry:

  @Article{,
    title = {Processing Ecological Data in {R} with the {mefa}
      Package},
    author = {P\'eter S\'olymos},
    journal = {Journal of Statistical Software},
    year = {2009},
    volume = {29},
    number = {8},
    pages = {1--28},
    url = {http://www.jstatsoft.org/v29/i08/},
  }