citHeader("To cite ggplot2 in publications, please use:")

citEntry(entry = "book",
  author = "Hadley Wickham",
  title = "ggplot2: elegant graphics for data analysis",
  publisher = "Springer New York",
  year = "2009",
  isbn = "978-0-387-98140-6",
  url = "http://had.co.nz/ggplot2/book",
  textVersion = "H. Wickham. ggplot2: elegant graphics for data analysis. Springer New York, 2009."
)