Multi-Proxy Multi-Signcryption Scheme from Pairings
  A first multi-proxy multi-signcryption scheme from pairings, which efficiently combines a multi-proxy multi-signature scheme with a signcryption, is proposed. Its security is analyzed in detail. In our scheme, a proxy signcrypter group could be authorized as a proxy agent by the cooperation of all members in the original signcrypter group. Then the proxy signcryptions can be generated by the cooperation of all the signcrypters in the authorized proxy signcrypter group on behalf of the original signcrypter group. The correctness and the security of this scheme are proved. 
Liu Jun-Bao, Xiao Guo-Zhen