Jingliang Zhang Lizhen Ma Rong Sun Yumin Wang More Efficient VLR Group Signature Satisfying Exculpability. 1831-1835 2008 91-A IEICE Transactions 7 http://dx.doi.org/10.1093/ietfec/e91-a.7.1831 db/journals/ieicet/ieicet91a.html#ZhangMSW08