@article{oai:tsukuba.repo.nii.ac.jp:00017216,
 author = {Ishii, Naonori},
 issue = {1},
 journal = {Tsukuba Journal of Mathematics},
 month = {Jun},
 pages = {55--89},
 title = {A certain graph obtained from a set of several points on a Riemann surface},
 volume = {23},
 year = {1999}
}