1. Hall, M. L. What’s Your IBU?; Home Brewers Association Zymurgy Special, 1997; pp 55–67.
2. Fundamentals of beer and hop chemistry
3. Equilibrium moisture content of hops
4. ASBC Methods of Analysis, online. Method Hops—14.
α
-acids & ß -acids in Hops and Hop. Approved 2010; American Society of Brewing Chemists: St. Paul, MN, U.S.A., 2010.