To cite vdg in publications use:

Schoonees P, le Roux N, Coetzer R (2016). “Flexible Graphical Assessment of Experimental Designs in R: The vdg Package.” Journal of Statistical Software, 74(3), 1–22. doi:10.18637/jss.v074.i03.

Corresponding BibTeX entry:

  @Article{,
    title = {Flexible Graphical Assessment of Experimental Designs in
      {R}: The {vdg} Package},
    author = {Pieter Schoonees and Ni\"el {le Roux} and Roelof
      Coetzer},
    journal = {Journal of Statistical Software},
    year = {2016},
    volume = {74},
    number = {3},
    pages = {1--22},
    doi = {10.18637/jss.v074.i03},
  }