Composition #10: Caprioli, Giovanni., Cortese, Manuela., Maggi, Filippo., Minnetti, Caterina., Odello, Luigi., Sagratini, Gianni., Vittori, Sauro. Quantification of caffeine, trigonelline and nicotinic acid in espresso coffee: the influence of espresso machines and coffee cultivars . international journal of food sciences and nutrition, 2014, vol. 65, no. 4, p. 465–469. DOI: 10.3109/09637486.2013.873890.
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