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2. ibidem (1978).
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4. C. M. Goodall, W. Lijinsky and L. Tomatis, Tumorigenicity of N–nitrosohexamethyleneimine, Cancer Res., 28: 1217–1220 (1968).
5. G. M. Bonser, D. B. Clayson, J. W. Jull and L. N. Pirah, The carcinogenic activity of 2–naphthylamine, Br. J. Cancer, 10: 533–538 (1956).