To cite package 'RMark' in publications use:

  Laake J (2013). “RMark : An R Interface for Analysis of
  Capture-Recapture Data with MARK.” AFSC Processed Rep. 2013-01,
  Alaska Fish. Sci. Cent., NOAA, Natl. Mar. Fish. Serv.
  <https://apps-afsc.fisheries.noaa.gov/Publications/ProcRpt/PR2013-01.pdf>.

A BibTeX entry for LaTeX users is

  @TechReport{,
    author = {Jeff Laake},
    type = {{AFSC} Processed Rep.},
    number = {2013-01},
    institution = {Alaska Fish. Sci. Cent., {NOAA}, Natl. Mar. Fish. Serv.},
    pages = {25},
    title = {{RMark} : An R Interface for Analysis of Capture-Recapture Data with MARK},
    url = {https://apps-afsc.fisheries.noaa.gov/Publications/ProcRpt/PR2013-01.pdf},
    year = {2013},
  }