@inproceedings{paper65,
  title = "Physical Traces: Quantum vs. Classical Information Processing",
  author = "S. Abramsky and B. Coecke",
  year = "2003",
  booktitle = "Electronic Notes in Theoretical Computer Science",
  pages = "1-26",
  url = "http://www1.elsevier.com/gej-ng/31/29/23/131/23/24/69002.pdf",
  volume = "69",
}