Qiong Huang Duncan S. Wong Jin Li Yiming Zhao Generic Transformation from Weakly to Strongly Unforgeable Signatures. 240-252 2008 23 J. Comput. Sci. Technol. 2 http://dx.doi.org/10.1007/s11390-008-9126-y db/journals/jcst/jcst23.html#HuangWLZ08