1. Key world energy statistics 2018,2018
2. Global Status Report 2018: towards a zero-emission, efficient and resilient buildings and construction sector,2018
3. Hamilton I, Rapf O. Global status report for buildings and construction 2020: towards a zero-emissions, efficient and resilient buildings and construction sector. United Nations Environment Programme (UNEP) Global Alliance for Buildings and Construction (GlobalABC); 2020. Available at: https://globalabc.org/news/launched-2020-global-status-report-buildings-and-construction
4. Degree-days: theory and application (TM41:2006),2006
5. Degree Days. Degree days calculated accurately for locations worldwide; 2020. http://www.degreedays.net