Fig. 17. The local deformations (I)-(IV), where δ∈{+1,−1} and i is a positive integer, and we omit the orientations of the arcs and some of the labels of the regions. The deformation (II) is applicable only if the resulting graph admits the induced orientation.

Kyungpook Mathematical Journal 2021;61:409~439 https://doi.org/10.5666/KMJ.2021.61.2.409

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