1. Agricultural statistics, United Kingdom, 1984, (HMSO 1986)
2. Output and utilisation of farm produce in the United Kingdom, 1978 to 1984, (HMSO 1985)
3. Annual abstract of statistics number 122, (HMSO 1986)
4. Sainsbury, D.: Poultry Health and Management, (Collins Professional and Technical Books, London 1980)