1. Sum of edge lengths of a multigraph drawn on a convex polygon;Ito;Computational Geometry,2003
2. H. Ito, Three equivalent partial orders on graphs with real edge-weights drawn on a convex polygon, Discrete and Computational Geometry: Proceedings of JCDCG 2004, Lecture Notes in Computer Science, vol. 3742, Springer, Berlin, 2005, pp. 123–130.
3. H. Ito, H. Nagamochi, Can a hypergraph cover every convex polygon, Proceedings of the Third Hungarian–Japanese Symposium on Discrete Mathematics and Its Applications, Sanjo Conference Hall, The University of Tokyo, January 21–24, 2003, pp. 293–302.
4. H. Ito, H. Nagamochi, Comparing hypergraphs by areas of hypergraphs drawn in a convex polygon, Discrete and Computational Geometry: Proceedings of JCDCG 2002, Lecture Notes in Computer Science, vol. 2866, Springer, Berlin, 2003, pp. 176–181.
5. Lengths of tours and permutations on a vertex set of a convex polygon;Ito;Discrete Appl. Math.,2001