To cite package 'BRAIN' in publications use:

  Claesen J., Dittwald P., Burzykowski T. and Valkenborg D. An
  efficient method to calculate the aggregated isotopic distribution
  and exact center-masses. JASMS, 2012, doi:10.1007/ s13361-011-0326-2

A BibTeX entry for LaTeX users is

  @Article{,
    title = {An efficient method to calculate the aggregated isotopic distribution and exact center-masses},
    author = {J. Claesen and P. Dittwald and T. Burzykowski and D. Valkenborg},
    journal = {JASMS},
    year = {2012},
  }

  Dittwald P., Claesen J., Burzykowski T., Valkenborg D., Gambin A.
  BRAIN: a universal tool for high-throughput calculations of the
  isotopic distribution for mass spectrometry. Anal Chem., 2013, doi:
  10.1021/ac303439m

A BibTeX entry for LaTeX users is

  @Article{,
    title = {BRAIN: a universal tool for high-throughput calculations of the isotopic distribution for mass spectrometry},
    author = {P. Dittwald and J. Claesen and T. Burzykowski and D. Valkenborg and A. Gambin},
    journal = {Anal Chem.},
    year = {2013},
  }

To obtain the references in BibTex format, enter
'toBibtex(citation("fastseg"))'