https://digilab.uwr.edu.pl/en/dlibra/publication/104490/protonated-o-semiquinone-radical-as-a-mimetic-of-the-humic-acids-native-radicals-a-dft-approach-to-the-molecular-structure-and-epr-properties-witwicki
Protonated o-semiquinone radical as a mimetic of the humic acids native radicals : a DFT approach...
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