1. Bonaccorso B, Bordi I, Cancelliere A, Rossi G, Sutera A (2003) Spatial variability of drought: an analysis of SPI in Sicily. Water Resour Manag 17:273–296
2. Bordi I, Fraedrich K, Petitta M, Sutera A (2005) Methods for predicting drought occurrences. In: Proc. of the 6th international conference of the European water resources association Menton, France, pp 7–10 September 2005
3. Bremaud P (1999) Markov chains, Gibbs fields, Montecarlo simulation and queues, Springer, The Netherlands
4. Brockwell PJ, Davis RA (1996) Introduction to time series and forecasting Springer-Verlag ed., New York, pp 1–422
5. Cancelliere A, Di Mauro G, Bonaccorso B, Rossi G (2005) Stochastic forecasting of standardized precipitation index. Proc. of XXXI IAHR Congress “Water engineering for the future: choice and challenges”. Seoul, Korea, 11–16 September 2005, pp 3252–3260