1. Anon . 1994 . Fertiliser Recommendations for Agricultural and Horticultural Crops: Reference Book 209 . London: The Stationery Office. 112 pp.
2. Anon . 2000 . Potato variety handbook 2000, NIAB recommended list of potatoes . Cambridge: National Institute of Agricultural Botany. 60 pp.
3. G R. Beard, 1988 . The soils of Harper Adams University College, Newport, Shropshire.Soil Survey and Land Research Centre, Contract No. 45.