To cite msap in publications use:

Perez-Figueroa (2013). msap: a tool for the statistical analysis of methylation-sensitive amplified polymorphism data. Molecular Ecology Resources. doi:10.1111/1755-0998.12064

Corresponding BibTeX entry:

  @Article{,
    title = {msap: a tool for the statistical analysis of
      methylation-sensitive amplified polymorphism data},
    author = {A. Perez-Figueroa},
    journal = {Molecular Ecology Resources},
    year = {2013},
    doi = {doi: 10.1111/1755-0998.12064},
  }