1. (1) CNS 2396, Protective Helmets for Motor Cyclists, (1998), Chinese Standard Institution, Taipei.
2. (2) JIS T 8133, Protective Helmets for Vehicle Users, (1994), Japanese Industrial Standard, Tokyo.
3. (3) E.C.E.R 22, Uniform Provisions Concerning the Approval of Protective Helmets and Their Visors for Drivers and Passengers of Motorcycles and Mopeds, (1995), Geneva.
4. (4) FMVSS 218, Motorcycle Helmets, (1992), Federal Motor Vehicle Safety Standard, Washington.
5. (5) Kingsbury, H.B. and Rohr, P.R., Structure Characteristics of Motorcycle Helmets, SAE paper 810372, (1981).