To cite DiagTest3Grp in publications use:

Jingqin Luo, Chengjie Xiong (2012). DiagTest3Grp: An R Package for Analyzing Diagnostic Tests with Three Ordinal Groups. Journal of Statistical Software, 51(3), 1-24. URL http://www.jstatsoft.org/v51/i03/.

Corresponding BibTeX entry:

  @Article{,
    title = {{DiagTest3Grp}: An {R} Package for Analyzing Diagnostic
      Tests with Three Ordinal Groups},
    author = {Jingqin Luo and Chengjie Xiong},
    journal = {Journal of Statistical Software},
    year = {2012},
    volume = {51},
    number = {3},
    pages = {1--24},
    url = {http://www.jstatsoft.org/v51/i03/},
  }