Weir, W. W., & Gregory, R. W. (1938). Productive soils: The fundamentals of successful soil management and profitable crop production. J.B. Lippincott company.
Stile di citazione ChicagoWeir, Wilbert Walter, e R. W. Gregory. Productive Soils: The Fundamentals of Successful Soil Management and Profitable Crop Production. Chicago, Philadelphia [etc.]: J.B. Lippincott company, 1938.
Citazione MLAWeir, Wilbert Walter, e R. W. Gregory. Productive Soils: The Fundamentals of Successful Soil Management and Profitable Crop Production. J.B. Lippincott company, 1938.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.