Multipartite entanglement purification with quantum nondemolition detectorsY. B. Sheng, F. G. Deng, B. K. Zhao, T. J. Wang and H. Y. ZhouEur. Phys. J. D, 55 1 (2009) 235-242DOI: https://doi.org/10.1140/epjd/e2009-00237-y