1. https://www.iea.org/buildings/.
2. https://www.statista.com/statistics/731858/projected-global-building-floor-area-growth-by-region/.
3. World business council for sustainable development, August 2009;Energy Efficiency in Buildings,2009
4. http://www.coolingindia.in/blog/post/id/9983/energy-saving-in-the-hvac-industry.
5. https://www.bp.com/content/dam/bp/en/corporate/pdf/energy-economics/energy-outlook/bp-energy-outlook-2018.pdf.