1. 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
2. The principles of irrigation practice Creator: Widtsoe, John Andreas, 1872-1952. Collection: Core Historical Literature of Agriculture Publisher: Macmillan, Publication Place: New York : Date: 1914 Format: Book