Biendl, Martin, and Bob Foster. “New International Calibration Standard (ICE-4) for HPLC Analysis of α- and β-Acids: Submitted on Behalf of the International Hop Standards Committee”. BrewingScience 71, no. 7/8 (August 31, 2018): 73. Accessed May 30, 2026. https://brewingscience.de/index.php/brewingscience/article/view/269.