Edge-disjoint paths in a grid bounded by two nested rectangles. - Hitoshi Suzuki; Akira Ishiguro; Takao Nishizeki (Discret. Appl. Math., 1990)

Variable-Priority Queue and Doughnut Routing. - Hitoshi Suzuki; Akira Ishiguro; Takao Nishizeki (J. Algorithms, 1992)