@article{oai:ir.kagoshima-u.ac.jp:00006984,
 author = {ISOKAWA, Yukinao and SAKAI, Koukichi},
 journal = {鹿児島大学理学部紀要, Reports of the Faculty of Science, Kagoshima University},
 month = {Dec},
 pages = {9--17},
 title = {Shape of the Apollonian Packing in the Euclidean Plane},
 volume = {31},
 year = {1998}
}