1. Hawking SW. http://www.independent.co.uk/news/science/stephen-hawking-pollution-stupidity-artificial-intelligence-warfare-biggest-threats-mankind-a7106916.html. Accessed 28 June 2016.
2. World Aluminum. Primary Aluminum Production. http://www.world-aluminium.org/statistics/#linegraph. Accessed 22 Jan 2018.
3. Hungary (2018) https://www.google.com.br/search?q=Hungaria+ecological+tragedy+2010&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjg7rTGjI3ZAhUJEJAK HeP8DxIQsAQIKg&biw=1813&bih=830#imgrc=endIlYzzpvAZ4M:
4. Mariana. https://www.theguardian.com/sustainable-usiness/2015/nov/25/brazils-mining-tragedy-dam-preventable-disaster-samarco-vale-bhp-billiton
5. Sushil S, Batra VS (2008) Catalytic applications of red mud, an aluminum industry waste: a review. J Appl Catalysis B: Environ 81:1