A Gamified Flexible Transportation Service for On-Demand Public Transport. - Richardos Drakoulis; Francesco Bellotti; Ioannis Bakas; Riccardo Berta; Pratheep Kumar Paranthaman; Gautam Ravindra Dange; Panagiotis Lytrivis; Katia Pagle; Alessandro De Gloria; Angelos Amditis (IEEE Trans. Intell. Transp. Syst., 2018)