1. J Mortatti and Nascimento Fillo, Energia Nuclaer-e-Agricultura Brazil 5, 18 (1983)
2. E S de Barros-Ferraz and M A Rezenda, Proceedings of the General Congress of Nuclear energy (Rio de Janeiro) 2, 443 (1986)
3. O Aguiar and E S Barros-Ferraz, Energia Nuclaer-e-Agricultura Brazil 3, 87 (1981)
4. de Miranda, M Regina and E M Pascholati, Proceedings of the 4th Brazilean Meeting on Nuclear Applications (Rio de Janeiro) 2, 904 (1977)
5. R D Evans, The atomic nucleus (McGraw Hill, New Delhi, 1955) p. 713