To cite the LPmerge package in publications use:

Endelman,J.B. and C. Plomion (submitted) LPmerge: an R package for merging genetic maps by linear programming.

Corresponding BibTeX entry:

  @Article{,
    title = {LPmerge: an R package for merging genetic maps by linear
      programming},
    author = {J. B. Endelman and C. Plomion},
    year = {2013},
    journal = {Submitted},
  }