1. Dep. of Business Economics and Management, Division of Food Production and SocietyNorwegian Institute of Bioeconomy ResearchOsloNorway
2. Dep. of Agricultural and Consumer EconomicsUniv. of Illinois at Urbana‐ChampaignUrbanaIL61801
3. Dep. of AgricultureIllinois State Univ.NormalIL61790