7Steve Butzen and Meredith Cummings, Corn grain protein -understanding the nutritional profde of corn grain and the effects of management and growing conditions on nutritional quality, crop insights,2001, 9 (11): (Pioneer website).
8Ahamadi M, Wiebold W J, Beuerlein J E, et al. Agronomic practices that affect corn kernel characteristics. Agronomy Journal, 1993, 85:615-619.