PCG-ZHAW_unused_CERs_final_clean_PAC.pdf
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(surrendered until 2012, exchanged for EUAs since 2013) by the end of 2019, of which
0.964 billion were CERs (Nissen et al. 2020, p.29 f.). Given that the actual use of CERs will be finetuned until the very
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