To cite ecp in publications use:

Nicholas A. James, David S. Matteson (2014). ecp: An R Package for Nonparametric Multiple Change Point Analysis of Multivariate Data. Journal of Statistical Software, 62(7), 1-25. URL http://www.jstatsoft.org/v62/i07/.

Corresponding BibTeX entry:

  @Article{,
    title = {{ecp}: An {R} Package for Nonparametric Multiple Change
      Point Analysis of Multivariate Data},
    author = {Nicholas A. James and David S. Matteson},
    journal = {Journal of Statistical Software},
    year = {2014},
    volume = {62},
    number = {7},
    pages = {1--25},
    url = {http://www.jstatsoft.org/v62/i07/},
  }