On the Fish Base Crease Pattern and Its Flat Foldable Property

Mathematical terms, definitions, and several fundamental propositions or theorems without proof in this article are primarily quoted from two books: one by Honsberger [4] (its cover illustration in fact displays the property of isogonal conjugates in a triangle) and another edited by Iwata [6] (in Japanese-the work by Coxeter-Greitzer [2] is a good alternative in English). Technical terms on the topological graph theory are those used in the monograph by Gross-Tucker [3]. In addition, the websiteMathWorld [8] will be useful for looking up mathematical terms used in this article.