1. Official Methods of Analysis, 17th ed,2000
2. Physical And Mathematical Modelling of The Energy Requirements of the Outdoor Sow;Buckner;PhD Thesis. The University of Aberdeen,1996
3. Behaviour and shelter use by outdoor sows;Buckner;Appl Anim Behav Sci,1998
4. Outdoor Pigs - Their Nutrient Requirements, Appetite and Environmental Responses;Close;Rec Adv An,1993
5. Roughage for sows and finishing pigs (In Danish; Grovfoder til søer og slagtesvin);Danielsen;DJF report no 145,2001