To cite the package 'multmod' in publications use:

Pipper, C. and Ritz, C. (2009) An asymptotic correction for controlling the overall type I error when testing multiple outcomes Submitted manuscript

Corresponding BibTeX entry:

  @Unpublished{,
    title = {An asymptotic correction for controlling the overall type
      I error when testing multiple outcomes},
    author = {C. B. Pipper and C. Ritz},
    year = {2009},
    note = {Submitted manuscript},
  }