@article{oai:tsukuba.repo.nii.ac.jp:00028599,
 author = {Nemoto, Noriko},
 journal = {Tsukuba English Studies},
 month = {Feb},
 pages = {21--36},
 title = {<Articles> On Visual Paths Associated with Visible from and Visible to},
 volume = {29},
 year = {2011}
}