To cite package marmap in publications, use:

Eric Pante, Benoit Simon-Bouhet (2013) marmap: A Package for Importing, Plotting and Analyzing Bathymetric and Topographic Data in R. PLoS ONE 8(9): e73051. doi:10.1371/journal.pone.0073051

Corresponding BibTeX entry:

  @Article{,
    title = {marmap: A Package for Importing, Plotting and Analyzing
      Bathymetric and Topographic Data in R},
    author = {Eric Pante and Benoit Simon-Bouhet},
    year = {2013},
    journal = {PLoS ONE},
    volume = {8},
    number = {9},
    pages = {e73051},
    note = {doi:10.1371/journal.pone.0073051},
  }