Information leak in Liu et al.’s quantum private comparison and a new protocol Y.B. Li, Q.Y. Wen, F. Gao, H.Y. Jia and Y. Sun Eur. Phys. J. D, 66 4 (2012) 110 Published online: 30 April 2012 DOI: 10.1140/epjd/e2012-30065-9