1. Maximum permissible body burdens and maximum permissible concentration of radionuclides in air and in water for occupational exposure. National Bureau of Standards Handbook 69. U.S. Government Printing Office Washington D.C. 1963.
2. Report of the United Nations Scientific Committee on the Effects of Atomic Radiation General Assembly Official Records 13th Session Supplement No. 17 (A/3838) 1958; 17th Session Supplement No. 16 (A/5216) 1962; 19th Session Supplement No. 14 (A/5814) 1964 United Nations New York.
3. Klement A. W. Jr. etal Estimates of ionizing radiation doses in the United States 1960-2000 (ORP/CSD72-1). U.S. Environmental Protection Agency Rockville Md. 1972 (a) p. 13; (b) p. 12; (c) p.22.
4. Spiers F. W. Radioisotopes in the Human Body. Physical and Biological Aspects Academic Press New York 1972.
5. Eisenbud M. Environmental Radioactivity. McGraw-Hill New York 1963 (a) p. 136; (b) p. 156; (c) p. 157; (d) p. 280; (e) p. 201; (f) p. 211; (g) p. 232.