1. Better, M.L. & Ross, M. (1992). Light vehicles: Policies for reducing their energy use and environmental impacts. Energy and Environment, edited by Byrne, J. & Rish, D., Transaction Publishers, pp 187–233.
2. Census & Statistics Department (1993). Hong Kong Monthly Digest of Statistics, Hong Kong Government Printer.
3. Chung, F. (1993). Enviropmental impact of fossil fuel use in Hong Kong - A comparative analysis. Green Productivity, HKPC. No.2, pp 8–19.
4. Deakin, E. (1993). Policy responses in the USA. Transport Environment and Sustainaple Development, edited by Banister, D. & Button, K., E & FN Spon., pp 79–101.
5. Environmental Protection Department (1989). Environment Hong Kong 1989.