SPIE Proceedings [SPIE Optical Materials Technology for Energy Efficiency and Solar Energy - Toulouse-Labege, France (Monday 18 May 1992)] Optical Materials Technology for Energy Efficiency and Solar Energy Conversion XI: Selective Materials, Concentrators and Reflectors, Transparent Insulation and Superwindows - Advanced glazing and associated materials for solar and building applications: International Energy Agency Solar Heating and Cooling Program Task 18