1. Department of Computer Information Systems and Quantitative Methods, Texas State University, San Marcos, TX
2. MOX- Modeling and Scientific Computing, Department of Mathematics, Politecnico di Milano, Milan, Italy
3. Istituto di Matematica Applicata e Tecnologie Informatiche, Consiglio Nazionale delle Ricerche, Milan, Italy
4. Department of Decision Sciences, George Washington University, Washington, DC