To cite edcc in publications use:

Weicheng Zhu, Changsoon Park (2013). edcc: An R Package for the Economic Design of the Control Chart. Journal of Statistical Software, 52(9), 1-24. URL http://www.jstatsoft.org/v52/i09/.

Corresponding BibTeX entry:

  @Article{,
    title = {{edcc}: An {R} Package for the Economic Design of the
      Control Chart},
    author = {Weicheng Zhu and Changsoon Park},
    journal = {Journal of Statistical Software},
    year = {2013},
    volume = {52},
    number = {9},
    pages = {1--24},
    url = {http://www.jstatsoft.org/v52/i09/},
  }