1. Campbell's 1907 soil culture manual: a complete guide to scientific agriculture as adapted to the semi-arid regions : the proper fitting of the soil for the conservation and control of moisture and the development of soil fertility ; how moisture moves in the soil by capillary attraction, percolation and evaporation ; the relation of water and air to plant growth, and how this may be regulated by cultivation Creator: Campbell, Hardy Webster, 1850- Collection: Core Historical Literature of Agriculture Publisher: H. W. Campbell, Publication Place: Lincoln, Neb. : Date: 1907 Format: Book
2. Dry-farming: a system of agriculture for countries under a low rainfall / Creator: Widtsoe, John Andreas, 1872-1952. Collection: Core Historical Literature of Agriculture Publisher: The Macmillan Company, Publication Place: New York : Date: 1911 Format: Book