Paper  bibtex   

@InProceedings{Karavirta:survey,
  author = 	 {Ville Karavirta and Ari Korhonen and Petri Tenhunen},
  title = 	 {Survey of Effortlessness in Algorithm Visualization Systems},
  booktitle = {Proceedings of the Third Program Visualization Workshop},
  pages = 	 {141--148},
  year = 	 {2004},
  address = 	 {The University of Warwick, UK},
  month = 	 {July},
  url = {http://www.cs.hut.fi/Research/SVG/publications/p20.pdf}
}