1. Barac, C., Elliott, D., & Spencer, L. (1983). Public Awareness of Renewable Energy; a Pilot Study. International Journal of Ambient Energy, 4(4), 199–211.
2. Bondi, H. (1981). Tidal Power from the Severn Estuary, Energy Paper 46. London: Department of Energy.
3. Boyle, S. (1988). An Alternative Energy Path for the UK. London: Friends of the Earth.
4. Calder, R. (1938, January 29). Mighty Engines Driven by the Moon. Modern Wonders.
5. Challis, A. (1983). Comment at a Meeting of the All Party Parliamentary Group for Energy Studies (PGES), Oct. as Reported in NATTA Newsletter 11, Sept-Oct 1984. Full Text in Energy Focus Journal, Issue 1, Longmans.