Every reference with a DOI in the deposited reference list resolved to a known
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Characterization of naphthenic acids in crude oils and naphthenates by electrospray ionization FT-ICR mass spectrometry
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no DOI — not checkedMaria D.L.M. De Chamorro, M.C. Romano, Simultaneous demetallization and desulfurization of carbonaceous materials via microwaves, US patent 6068737, 2000.
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