Lockhart, J. A. R. Introduction to crop husbandry : including grassland / by J.A.R. Lockhart and A.J.L. Wiseman. - 6th ed. - Oxford, England : Pergamon, c1988. - xiii, 319 p. : ill. ISBN: 0080342019 Subjects--Topical Terms: Crops.Agriculture.Crops--Great Britain.Agriculture--Great Britain.