1. 1) International Organization for Standardization (ISO), “Safety of toys—Part 3: Migration of certain elements,” ISO 8124-3:2010(E), Switzerland, 2010.
2. 2) Consumer Safety Section, Consumer Affairs Division, Bureau of Citizens and Cultural Affairs, Tokyo Metropolitan Government, Tashikana Me, 241, 40-42 (2006).
3. 3) Office of Chemical Safety, Evaluation and Licensing Division, Pharmaceutical and Food Safety Bureau, Ministry of Health, Labour and Welfare: 〈http://www.mhlw.go.jp/shingi/2006/06/dl/s0613-7g.pdf〉, cited 19 April, 2012.
4. 4) Isama K., Kaniwa M., Tsuchiya T., Jpn. J. Toxicol., 19, 409-411 (2006).
5. 5) Isama K., Kaniwa M., Tsuchiya T., Jpn. J. Toxicol., 21, 393-395 (2008).