6Hai Yang, Yan Wing Lau, Sze Chun Wong, et al. A macroscopic taxi model for passenger demand, taxi utilization and level of services [J]. Transportation, 2000(6): 317-340.
7Jean-Fran ois Cordeau, Gilbert Laporte. The dial -a-ride problem: models and algorithms [J]. Annals of Operations Research, 2007(9): 29-46.
