References
- Ewa , I.O.B. and Dim , L. A. 1989 . Major, Minor and Trace Elemant Determinations from a Nigerian Aquatic Sediment . J. Environ. Sci. Health , A24 ( 3 ) : 243 – 254 .
- Miller , J. M. , Roberts , P. D. , Symons , G. D. , Merrill , H. H. and Normald , K. R. 1977 . Muclear Techniques and Mineral Resources , 465 Vienna : I.A.E.A .
- Ogugbuaja , V. O. 1985 . Statistical Analysis of Heavy metal concentrations from lake sediments . J. Environ. Sci. Health , A20 ( 5 ) : 529 – 554 .
- Vebster , R. 1978 . Optimally Partitioning of Soil Transects . J. of Soil Sci. , 29 : 388 – 402 .
- International Atonic Energy Agency . 1970 . Reference Methods for Marine Radioactivity Studies , Vienna : I.A.E.A. .
- Vara , J. H. 1963 . Hierarchical Grouping to Optimise an Objective Function . J. of the American Statistical Assoc. , 58 : 236 – 244 .
- Wishart , D. 1982 . CLUSTAN User Manual: Program Library Unit Edinburgh University Edinburgh, Scotland
- 1985 . SAS User's Guide: Statistics. , Version 5 Edition , Cary, NC. : SAS Institute Inc. .
- Op de Beck , J. 1984 . Clustering of Samples and Elements Based on Multi‐Variable Chemical Data . Proc. 5th Int. Conf. on Nuclear Methods in Environmental and Energy Research . April 1984 , Columbia, U.S.A. Univ. of Missouri .
- Briggs , D. 1977 . Sediments: Sources and Methods in Geography , London : Butterworths .
- Morse , R. H. 1971 . Comparison of Geochemical Prospecting Methods using Radon and Uranium . Geochem. Explor. C. I.M. Spec. , 11 : 215 – 230 .
- Guimond , R. J. and Hardin , J.N. 1989 . Radioactivity Released from Phosphate‐Containing Fertilizers and from Cypsum . Int. J. Radiat. Appl. Instrum., Part C., Radiat. Phys. Chem. , 34 ( 2 ) : 309 – 315 .
- Pfister , H. , Phillip , O. and Pauly , H. 1976 . Population Dose from Natural Radlonuclide in Phosphate Fertilizers . Radiol. Environ. Biophys. , 13 : 217