V. Jerkovic and S. C. Sonia Collin, “The cis-resveratrol Concentration is Proposed as a New Indicator of the Hop Freshness”, BrSc, vol. 62, no. 7/8, pp. 141–146, Aug. 2009, Accessed: May 30, 2026. [Online]. Available: https://brewingscience.de/index.php/brewingscience/article/view/476