@article{leskovec2008planetary,
  author = {Leskovec, J. and Horvitz, E.},
  interhash = {27d7144813bb85492b18cad6cf6525e7},
  intrahash = {958ce0f9954243d9b27e7e7fee063b01},
  publisher = {ACM New York, NY, USA},
  title = {{Planetary-scale views on a large instant-messaging network}},
  url = {http://scholar.google.de/scholar.bib?q=info:dvYmn_qj6NQJ:scholar.google.com/&output=citation&hl=de&as_sdt=2000&ct=citation&cd=0},
  year = 2008
}