1. International University of La Rioja, Faculty of Business and Communication, Department of Business Organization, Marketing and Market Research, Av. de la Paz, 137, 26006 Logroño, Spain
2. Rey Juan Carlos University, Faculty of Social Sciences and Law, Department of Business Economics, Paseo Artilleros s/n, Madrid 28032, Spain
3. NOVA University Lisbon, Faculdade de Ciências e Tecnologia, Campus FCT/UNL, UNIDEMI, Monte da Caparica, 2829-519 Caparica, Portugal
4. University of Extremadura, Faculty of Business, Finance and Tourism, Department of Business Management and Sociology, 10071 Caceres, Spain