1. E. Albini, L. Mascaro, S. Bellini, Health Phys., 59 (1990) 455.
2. A. Gedikoglu, B. Sipahi, Health Phys., 56 (1989) 97.
3. J. J. Fletcher, M. Almagrahi, A. Kikli, H. El Shamis, M. Hadia, Report on Radioactivities in Tobacco and Cigarettes, TNRC, Libya, 1991.
4. J. Last, Radiation Contamination of Food, in: M. Rosenau, Public Health and Preventive Medicine, 11th ed., Appelton-Century-Croft, New York, 1973, p. 884.
5. IAEA, A Basic Toxicity Classification of Radionuclides, Technical Report Series No. 15 Vienna, 1963.