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@article{schaeck200902,

  author = "Stefan Schaeckeler and Weijia Shang and Ruth Davis",

  title = "Visualization of Procedural Abstraction",

  journal = "Electronic Notes in Theoretical Computer Science",

  volume = "224",

  year = "2009",

  issn = "1571-0661",

  pages = "27--39",

  doi = {http://dx.doi.org/10.1016/j.entcs.2008.12.046},

  publisher = {Elsevier Science Publishers B. V.},

  address = {Amsterdam, The Netherlands, The Netherlands}
}