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2. Amnesty International. (2016).This is what we die for. Human rights abuses in the democratic republic of the Congo power the global trade in cobalt.https://www.amnestyusa.org/files/this_what_we_die_for_-_report.pdf
3. BGR. (2019).Fachinformationssystem Rohstoffe. unpublished. data status Jun 30.Hannover Germany.
4. Rare‐earth mining in China comes at a heavy cost for local villages;Bontron C.;The Guardian.,2012