1. Group housing of farrowing sows, health aspects of a new system;Algers,1991
2. Straw and food as reinforcers for prepartal sows;Arey;Appl. Anim. Behav. Sci.,1992
3. Effects of straw and unfamiliarity on fighting between newly mixed growing pigs;Arey;Appl. Anim. Behav. Sci.,1995
4. The application of biosecurity protocols in large production systems: experiences from the field;Baker,2004
5. The freedom farrowing system;Baxter;Farm Build. Progr.,1991