Composition #2: Wojtowicz, E., Zawirska-Wojtasiak, R., Przygoński, K., Mildner-Szkudlarz, S. Bioactive β-carbolines norharman and harman in traditional and novel raw materials for chicory coffee. food chemistry, 2015, vol. 175, p. 280–283. DOI: 10.1016/j.foodchem.2014.11.143.
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