1. Arik, A., 1992, Outlier Restricted Kriging: A New Kriging Algorithm for Handling of Outlier High Grade Data in Ore Reserve Estimation,in Y. C. Kim (Ed.),Proceedings of the 23rd International APCOM Symposium: Society of Mining Engineers, Littleton, CO, p. 181–187.
2. Armstrong, M., 1984, Common Problems Seen in Variograms: Math. Geol., v. 16, n. 3, p. 305–313.
3. Barnes, R. J., 1991, The Variogram Sill and the Sample Variance: Math. Geol., v. 23, n. 4, p. 673–678.
4. Billingsley, P., 1978,Ergodic Theory and Information: Robert E. Krieger Publishing Company, Huntington, NY, 193 p. (reprint of 1965 edition, John Wiley & Sons, New York).
5. Cramér, H., 1954,Mathematical Methods of Statistics: Princeton University Press, Princeton, NJ, 575 p.