Digital Economy. Emerging Technologies and Business Innovation 4th International Conference, ICDEc 2019, Beirut, Lebanon, April 15-18, 2019, Proceedings - Jallouli, Rim; Jallouli, Rim; Bach Tobji, Mohamed Anis; Bach Tobji, Mohamed Anis; Bélisle, Deny; Bélisle, Deny; Mellouli, Sehl; Mellouli, Sehl; Abdallah, Farid; Abdallah, Farid; Osman, Ibrahim; Osman, Ibrahim (Springer International Publishing : Imprint: Springer, 2019)