1. 1. Nihonyanagi, Y., Oshiro, M., Nagashima, M., et al.; A case of ileum perforation caused by accidental ingestion of a press-through package that could be diagnosable by abdominal CT. Journal of Abdominal Emergency Medicine, 28(1), pp.85-88, 2008. (in Japanese)
2. 2. Shimizu, K., Shimoyama, K., and Matsuo, M.; Accidental ingestion and aspiration of press-through-packages. Japanese Journal of Gerodontology, 27(1), 2012. (in Japanese)
3. 3. The Federation of Pharmaceutical Manufacturers’ Associations of Japan; Preventive measures for accidental ingestion of press-through packages. FPMAJ Publication, 587, 2010. (in Japanese)
4. 4. Consumer Safety Investigation Commission; Investigation cause investigation report based on Article 23 paragraph 1 of consumer safety law -the accidental ingestion of pharmaceutical products-, December 2015. (in Japanese)
5. 5. The Safety Committee of the Federation of Pharmaceutical Manufacturers’ Associations of Japan; A written inquest report regarding the prevention of accidental ingestion of pharmaceutical products by children, October 2017. (in Japanese)