@inproceedings{KP08,
  author = {Akinori Kawachi and Christopher Portmann},
  title = {On the Power of Quantum Encryption Keys},
  booktitle = {Post-Quantum Cryptography},
  year = 2008,
  pages = {165--180},
  publisher = {Springer},
  month = oct,
  series = {Lecture Notes in Computer Science},
  volume = 5299,
  doi = {10.1007/978-3-540-88403-3_12},
  eprint = {arXiv:0808.2869}
}