J. C. Ferreira et al.,  "Distributed multimodal journey planner based on mashup of individual planners’ APIs", in Highlights of Practical Applications of Cyber-Physical Multi-Agent Systems. PAAMS 2017. Communications in Computer and Information Science, Lopes F.,Bajo J.,Novais P.,Hallenborg K.,Del Val E.,Julian V.,Vale Z.,Pawlewski P.,Duque Mendez N.D.,Holmgren J.,Rocha A.P.,Mathieu P., Ed., Porto, Springer, 2017, vol.  722, pp. 307-314