1. Comisión Nacional del Mercado de Valores C/de Edison n°4 Madrid 28006 Spain
2. University of Oviedo Avda. del Cristo s/n Oviedo 33071 Spain
3. Florida Atlantic University 777 Glades Rd Boca Raton FL 33432 USA
4. Norwegian School of Economics Helleveien 30 Bergen 5045 Norway