Hseh, W. A., Ni, C., Hwang, J. J., Fang, S., Lin, S. P., Huang, T. W. and Chang, W. P. Evaluation of the frequencies of chromosomal aberrations in a population exposed to prolonged low dose-rate 60Co gamma-irradiation. Int. J. Radiat. Biol., 78: 625-633, 2002.