To cite fclust in publications use:

M.B. Ferraro, P. Giordani and A. Serafini (2019) fclust: An R Package for Fuzzy Clustering, The R Journal, 11, https://journal.r-project.org/archive/2019/RJ-2019-017/RJ-2019-017.pdf

Corresponding BibTeX entry:

  @Article{,
    title = {fclust: An R Package for Fuzzy Clustering},
    author = {M.B. Ferraro and P. Giordani and A. Serafini},
    journal = {The {R} Journal},
    year = {2019},
    volume = {11},
    url =
      {https://journal.r-project.org/articles/RJ-2019-017/RJ-2019-017.pdf},
  }