To cite phyloch in a publication use:

Heibl C (2008 onwards). “PHYLOCH: R language tree plotting tools and interfaces to diverse phylogenetic software packages. http://www.christophheibl.de/Rpackages.html.”

As phyloch is evolving quickly, you may want to cite also its version number (found with 'library(help = phyloch)').

Corresponding BibTeX entry:

  @Misc{,
    title = {PHYLOCH: R language tree plotting tools and interfaces to
      diverse phylogenetic software packages.
      http://www.christophheibl.de/Rpackages.html},
    author = {C. Heibl},
    year = {2008 onwards},
  }