Robert McGill and John W. Tukey and Wayne A. Larsen.
Variations of Box Plots.
In The American Statistician, vol. 32, no. 1, pp. 12--16, 1978.

Bibtex:

@Article{        mcgill:1978:VOBP,
  author = 	 "Robert McGill and John W. Tukey and Wayne A. Larsen",
  title = 	 "Variations of Box Plots",
  journal = 	 "The American Statistician",
  year = 	 "1978",
  volume = 	 "32",
  number = 	 "1",
  pages = 	 "12--16",
  month = 	 "February",
}