Li, Jiaoyang, Daniel Harabor, Peter J. Stuckey, Hang Ma, and Sven Koenig. 2019. “Symmetry-Breaking Constraints for Grid-Based Multi-Agent Path Finding”. Proceedings of the AAAI Conference on Artificial Intelligence 33 (01):6087-95. https://doi.org/10.1609/aaai.v33i01.33016087.