Applied stochastic models and data analysis : quantitative methods in business and
industry society : proceedings of the / IX International Symposium on Applied Stochastics
Models and Data Analysis (ASMDA-99) University of Lisbon, Portugal, June 14 - 17,
1999 ; edited by H. Bacelar-Nicolau, ...F. Costa Nicolau, ... J. Janssen, ..., 1999