1. American National Standards Institute, Inc. (ANSI), 1983. Rationales for ANSI A14.1-1981 (Wood Ladders), A14.2-1981 (Metal Ladders), and A14.5-1981 (Reinforced Plastic Ladders).
2. The Forces and Moments in the Leg During Level Walking;Bresler,1948
3. Occupational Biomechanics;Chaffin,1984
4. Ergonomic considerations related to selected fall prevention aspects of scaffolds and ladders as presented in OSHA Standard 29 CFR 1910 Subpart D;Chaffin,1979
5. Operator Grip Strength;Jack,1978