Yamanaka, K., Demaine, E., Horiyama, T., Kawamura, A., Nakano, S.- ichi, Okamoto, Y., … Uno, T. (2019). Sequentially Swapping Colored Tokens on Graphs. Journal of Graph Algorithms and Applications, 23(1), 3–27. https://doi.org/10.7155/jgaa.00482