National Research Council (U.S.). Subcommittee on Beef Cattle Nutrition. (1996). Nutrient requirements of beef cattle (7th rev. ed.). National Academy Press.
Dyfyniad Arddull ChicagoNational Research Council (U.S.). Subcommittee on Beef Cattle Nutrition. Nutrient Requirements of Beef Cattle. 7th rev. ed. Washington, D.C.: National Academy Press, 1996.
Dyfyniad MLANational Research Council (U.S.). Subcommittee on Beef Cattle Nutrition. Nutrient Requirements of Beef Cattle. 7th rev. ed. National Academy Press, 1996.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.