@article{WuZhouChenetal.2010,
  author    = {Ye Wu and Changsong Zhou and Maoyin Chen and Jinghua Xiao and J{\"u}rgen Kurths},
  title     = {Human comment dynamics in on-line social systems},
  doi       = {10.1016/j.physa.2010.08.049},
  url       = {http://www.sciencedirect.com/science/journal/03784371},
  year      = {2010},
}