To cite fuzzySim in publications use:

  Barbosa, A.M. (2015) fuzzySim: applying fuzzy logic to binary
  similarity indices in ecology. Methods in Ecology and Evolution,
  6(7), 853-858. DOI: 10.1111/2041-210X.12372. URL:
  https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/2041-210X.12372.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {{fuzzySim}: applying fuzzy logic to binary similarity indices in ecology},
    author = {{A. Marcia Barbosa}},
    journal = {Methods in Ecology and Evolution},
    year = {2015},
    volume = {6},
    number = {7},
    pages = {853-858},
    doi = {10.1111/2041-210X.12372},
  }