Mikyška, Alexandr, and Martin Dušek. “How Wort Boiling Process Affects Flavonoid Polyphenols in Beer”. KVASNY PRUMYSL 65, no. 6 (December 10, 2019): 192–200. Accessed February 17, 2020. http://kvasnyprumysl.eu/index.php/kp/article/view/205.