@article{1365777,
      recid = {1365777},
      author = {Khovanov, Mikhail,},
      title = {Extended graphical calculus for categorified quantum sl(2)  /},
      pages = {1 online resource (100 pages) :},
      note = {"September 2012, Volume 219, Number 1029 (second of 5  numbers)."},
      url = {http://library.usi.edu/record/1365777},
}