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References for REES from coal refuse

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• Luttrell, G.H., Kiser, M.J., Yoon, R.-H., Bhagavatula, A., Rezaee, M., and Honaker, R.Q., 2016, Concentrations of Rare Earth Elements generated by U.S. coal preparation plants: Proceedings of the 33rd Annual International Coal Preparation Conference, Louisville, Kentucky, Coal Prep, 2016, p. 35–41.
• Luttrell, G.H., Kiser, M.J., Yoon, R.H., Noble, A., Rezaee, M., Bhagavatula, A. and Honaker, R.Q., 2019, A field survey of rare earth element concentrations in process streams produced by coal preparation plants in the eastern USA: Mining, Metallurgy & Exploration, v. 36, p. 889–902.
• NETL, 2021a, Critical minerals and materials program: U.S. Department of Energy, National Energy Technology Laboratory website, https://netl.doe.gov/resource-sustainability/critical-minerals-and-materials/background#:~:text=REEs%20include%20lanthanum%20(La)%2C,)%20and%20yttrium%20(Y).
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• Zhang, W., Noble, A., Yang, X. and Honaker, R., 2020, A comprehensive review of rare earth elements recovery from coal-related materials: Minerals, v. 10, no. 5, 451.