1. Ballam, G. C., 1985. Laying hen nutrition: Integrating nutrition and management to affect egg size. Pages 58–68 in: Proceedings Degussa Technical Symposium. March 13, 1985. Degussa Corp., Fresno, CA.
2. Bell, D. D., and M. H. Swanson, 1975. Crowding of chickens in cages reduces your profits. University of California Leaflet 2273, Riverside, CA.
3. The requirement for sulfur amino acid by laying hens as influenced by the protein concentration;Calderon;Poultry Sci.,1990
4. An evaluation of layer performance in deep and shallow cages at different densities;Cunningham;Poultry Sci.,1981
5. The effects of strain and cage shape and density on performance and fearfulness of White Leghorn layers;Cunningham;Poultry Sci.,1982