R.S. RAMAKRISHNA; R.E. RAJASEELAN; J.M.T.B. KARUNARATNE; M. BALASUBRAMANIAM; R.R. BROOKS; D.E. RYAN; J. HOLZBECHER. A geochemical reconnaissance survey of Sri Lanka using panned mineral concentrates of stream sediments. Netherlands Journal of Geosciences, p. 237-244, 1 Jan. 1985.