An object oriented system using object-based, also
	called prototype-based, rather than class-based object oriented ideas.
c(
    person("Hadley", "Wickham", , "hadley@rstudio.com", "cre"),
    person("Gabor", "Grothendieck", , "ggrothendieck@gmail.com", "aut"),
    person("Louis", "Kates", role = "aut"),
    person("Thomas", "Petzoldt", role = "aut")
  )
Hadley Wickham [cre],
  Gabor Grothendieck [aut],
  Louis Kates [aut],
  Thomas Petzoldt [aut]