Flórez, J., Álvaro Torralba Arias de Reyna, J. García, C. Linares López, Ángel García-Olaya, and D. Borrajo. “Planning Multi-Modal Transportation Problems”. Proceedings of the International Conference on Automated Planning and Scheduling, vol. 21, no. 1, Mar. 2011, pp. 66-73, doi:10.1609/icaps.v21i1.13466.