1. United States Energy Information Administration. International energy outlook 2016 - Industrial sector energy consumption. 2016.
2. Weiss W., Spörk-Dür M. Solar heat world - Global market development and trends 2021. 2022.
3. Solar Payback. Solar heat for industry - South Africa. 2019.
4. Large-scale solar water heating in South Africa: status, barriers and recommendations;Joubert;Renew Energy,2016
5. Statistical release P3041.2 -;Statistics South;Manufacturing: production and sales,2021