http://www.margaretthatcher.org/document/107332
https://www.bmj.com/content/372/bmj.n314
https://yougov.co.uk/news/2017/04/26/voting-intention-conservatives-45-labour-29-25-26-/
https://orsted.com/-/media/WWW/Docs/Corp/COM/Barometer-campaign/Green-Energy-Barometer-2017_with-appendix.ashx?la=en&hash=65C5D0F30494C277249CA7622AF0229AD5B6D3CB