1. 3. Okuda K. Dental Plaque Bacteria. Ishiyaku Publishers, INC. Tokyo, 2000; 163-6. (in Japanese)
2. 4. Fukuizumi T, Kamihashi M, Kakinoki Y. What are the specific symptoms in the oral cavity in the elderly. In: Kakinoki Y, eds. Clinical Oral Health Care. Nissoken. Tokyo, 2000; 31-51. (in Japanese)
3. Swallowing abnormalities and their response to treatment in Parkinson's disease