Gao, Y., Li, Z., Vuong, T.-D. and Yang, L. 2019. Toric Mutations in the dP$_2$ Quiver and Subgraphs of the dP$_2$ Brane Tiling. The Electronic Journal of Combinatorics. 26, 2 (May 2019), P2.19. DOI:https://doi.org/10.37236/6825.