- Toru Akishita, Masanobu Katagi, Izuru Kitamura, and Tsuyoshi Takagi, Some improved algorithms for hyperelliptic curve cryptosystems using degenerate divisors, Information Security and Cryptology. ICISC 2004: 7th International Conference, Seoul, Korea, December 2–3, 2004, Lecture Notes in Comput. Sci., vol. 3506, Springer, Berlin, 2005, pp. 296.
- Masanobu Katagi, Toru Akishita, Izuru Kitamura, and Tsuyoshi Takagi, Efficient hyperelliptic curve cryptosystems using theta divisors, IEICE Trans. Fundamentals E89-A (2006), no. 1, 151–160.
- Masanobu Katagi, Izuru Kitamura, and Tsuyoshi Takagi, A point halving algorithm for hyperelliptic curves, http://eprint.iacr.org/2004/255.ps, 15 pages.