To cite FME in publications use:

Soetaert K, Petzoldt T (2010). “Inverse Modelling, Sensitivity and Monte Carlo Analysis in R Using Package FME.” Journal of Statistical Software, 33(3), 1–28. doi: 10.18637/jss.v033.i03.

Corresponding BibTeX entry:

  @Article{,
    title = {Inverse Modelling, Sensitivity and Monte Carlo Analysis in
      {R} Using Package {FME}},
    author = {Karline Soetaert and Thomas Petzoldt},
    journal = {Journal of Statistical Software},
    year = {2010},
    volume = {33},
    number = {3},
    pages = {1--28},
    doi = {10.18637/jss.v033.i03},
  }