To cite package 'cardidates' in publications use:

Rolinski, S., Horn, H., Petzoldt, T., & Paul, L. (2007): Identification of cardinal dates in phytoplankton time series to enable the analysis of long-term trends. Oecologia extbf{153}, 997 - 1008.

Corresponding BibTeX entry:

  @Article{,
    author = {Susanne Rolinski and Heidemarie Horn and Thomas Petzoldt
      and Lothar Paul},
    title = {Identifying cardinal dates in phytoplankton time series to
      enable the analysis of long-term trends},
    journal = {Oecologia},
    year = {2007},
    volume = {153},
    pages = {997--1008},
    number = {4},
    doi = {doi:10.1007/s00442-007-0783-2},
    keywords = {Spring mass development, Climate change, Saidenbach
      Reservoir, Limnology, Physical-biological coupling, Peak
      detection},
  }