To cite tourr in publications use:

Hadley Wickham, Dianne Cook, Heike Hofmann, Andreas Buja (2011). tourr: An R Package for Exploring Multivariate Data with Projections. Journal of Statistical Software, 40(2), 1-18. URL http://www.jstatsoft.org/v40/i02/.

Corresponding BibTeX entry:

  @Article{,
    title = {{tourr}: An {R} Package for Exploring Multivariate Data
      with Projections},
    author = {Hadley Wickham and Dianne Cook and Heike Hofmann and
      Andreas Buja},
    journal = {Journal of Statistical Software},
    year = {2011},
    volume = {40},
    number = {2},
    pages = {1--18},
    url = {http://www.jstatsoft.org/v40/i02/},
  }