S. Lichtenstein and J. R. Newman, “Empirical Scaling of Common Verbal Phrases Associated with Numerical Probabilities,” Psychonometric Science, Vol. 9, No. 10, 1967, pp. 563-564.
 S. Vick, “Dam Safety Risk Assessment: New Directions,” Water Power and Dam Construction, Vol. 49, No. 6, 1997, pp. 40-42
 E. Varanda, “Quantitative Landslide Risk Mapping for the 1st District of Petrópolis, Rio de Janeiro State, Using GIS,” Master’s Thesis, COPPE/Federal University of Rio de Janeiro, Rio de Janeiro, 2006.
 INPE (National Space Research Institute), “Spring Basic,” 2006. http://www.dpi.inpe.br/spring/portugues
 L. C. D. Oliveira, “Quantitative Risk Analysis of Mass Movements Using Bayesian Statistics,” Ph.D. Thesis, COPPE/Federal University of Rio de Janeiro, Rio de Janeiro, 2004.
 J. Stutz and P. A. Cheeseman, “Short Exposition on Bayesian Interference and Probability,” Computational Science Division, National Aeronautic and Space Administration Ames Research Centre, Data Learning Group, 1994.
 R. Fell and D. Hartford, “Landslides Risk Management,” Proceedings of the International Workshop on the Landslides Risk Assessment, Honolulu, 19-21 February 1997, pp. 51-109.
 Ministry of Cities, “Training in Mapping and Risk Management,” Cities Alliance, Brasília, 2006.
 Ministry of Cities, “Landslide Risk Prevention on Slopes: Guide for Preparing Local Government Policies,” Cities Alliance, Brasília, 2006.