To cite graphicsQC in publications use:

Paul Murrell, Stephen Gardiner (2009). Quality Control for Statistical Graphics: The graphicsQC Package for R. Journal of Statistical Software, 30(1), 1-28. URL http://www.jstatsoft.org/v30/i01/.

Corresponding BibTeX entry:

  @Article{,
    title = {Quality Control for Statistical Graphics: The {graphicsQC}
      Package for {R}},
    author = {Paul Murrell and Stephen Gardiner},
    journal = {Journal of Statistical Software},
    year = {2009},
    volume = {30},
    number = {1},
    pages = {1--28},
    url = {http://www.jstatsoft.org/v30/i01/},
  }