Song Han and Elizabeth Chang and Jie Wang and Wanquan Liu, A New Proxy Signature Scheme As Secure As ElGamal Signature. journal = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology. November 2007, vol. 11(11). 3525 - 3529 [viewed 28 March 2024]. Available from: https://publications.waset.org/pdf/3873.