1. Ishida, M. and Ikeda, H. (1956). Random number generator, Ann. Inst. Statist. Math., 8, 119-126.
2. Jansson, B. (1966). Random Number Generators, Victor Pettersons Bokindustri Aktiebolag, Stockholm, 283-305.
3. Kishimoto, S., Ikegami, T. and Hiramatsu, M. (1981). A generation method of physical random number sequence by using micro-computer, J. Japan Statist. Soc., 11, 2, 169-173.
4. Miyatake, O., Inoue, H. and Yoshizawa, Y. (1975). Generation of physical random numbers, Math. Japon., 20, 207-217.
5. Miyatake, O., Yoshizawa, Y., Inoue, H., Kumahora, H., Ichimura, M. and Kimura, H. (1979). On the generation and properties of physical random numbers, Math. Japon., 20, 369-376.