1. Invited Assistant Professor, Instituto Universitário de Lisboa (ISCTE-IUL), Business Research Unit (BRU-IUL), Ave. das Forças Armadas, 1649-026 Lisbon, Portugal (corresponding author).
2. Assistant Professor, Dipl-Eng, CERis, CESUR, Instituto Superior Técnico (IST), Univ. of Lisbon, Ave. Rovisco Pais, 1049-001 Lisbon, Portugal.