To cite Fisher-EM in publications use:

Charles Bouveyron, Camille Brunet (2012). Simultaneous model-based clustering and visualization in the Fisher discriminative subspace. Statistics and Computing, 22(1), 301-324.

Corresponding BibTeX entry:

  @Article{,
    title = {Simultaneous model-based clustering and visualization in
      the Fisher discriminative subspace},
    author = {Charles Bouveyron and Camille Brunet},
    journal = {Statistics and Computing},
    year = {2012},
    volume = {22},
    number = {1},
    pages = {301-324},
  }