Variation in the uranium isotopic ratios 234U/238U, 238U/total-U and 234U/total-U in Indian soil samples: Application to environmental monitoringS.K. Srivastava, A.Y. Balbudhe, K. Vishwa Prasad, P. Padma Savithri, R.M. Tripathi and V.D. PuranikRadioprotection, 48 2 (2013) 231-242DOI: https://doi.org/10.1051/radiopro/2012044