1. 1) Engineering News-Record, McGraw-Hill, 1988-1997,(Weekly).
2. 3) Law of Labor Safety and Sanitation, Ministry of Health, Labor and Welfare, Japan, Article 564th (in Japanese).
3. 4) Y. Kawajiri: Accident Report on Collapse of the Scaffolds by Strong Wind at Otemachi, Tokyo, Safety Engineering, vol. 18, No. 2, 1979, pp. 110-112 (in Japanese).
4. 5) Construction Industrial Safety Sanitation Yearbook (Annual), Japan Construction Safety and Health Association, 1989-1998, (in Japanese).