M. Navascués, Bae, J., Cirac, I. J., Lewenstein, M., Sanpera, A., and Acín, A.,
“Quantum Key Distillation from Gaussian States by Gaussian Operations”,
Physical Review Letters, vol. 94, p. 010502, 2005.
A. Acín, Bae, J., Bagan, E., Baig, M., Masanes, L., and Muñoz-Tapia, R.,
“Secrecy properties of quantum channels”,
Physical Review A (Atomic, Molecular, and Optical Physics), vol. 73, pp. 012327–5, 2006.