Drewnowski, Adam and Carmen Gomez-Carneros. “Bitter taste, phytonutrients, and the consumer: a review.” American Journal of Clinical Nutrition 72, No. 6 (December 2000): 1424–1435. https://ucanr.edu/datastoreFiles/608-47.pdf.
Keast, Russell, Thomas M. Canty, and Paul A.S. Breslin. “The Influence of Sodium Salts on Binary Mixtures of Bitter-tasting Compounds.” Chemical Senses 29, No. 5 (2004): 431–9. https://doi.org/10.1093/chemse/bjh045.