1. Cages: How can they be improved?;Tauson,1980
2. Svedberg, J., 1988. The connection between environment and foot conditions in laying hens: Environment and animal health. Pages 125–130 in: Proc. 6th Intl. Cong. on Anim. Hygiene, Skara, Sweden.
3. Broken bones in domestic fowl: Handling and processing damage in end-of-lay battery hens;Gregory;Br. Poultry Sci.,1989
4. Should cages for laying hens be banned or modified?;Appleby;Animal Welfare,1993
5. Behaviour, health, and integument of four hybrids of laying hens in modified and conventional cages;Abrahamsson;Br. Poultry Sci.,1996