Não informado. (1937). Soils and Fertilizers: Abstracts of world literature. Commonwealth Agricultural Bureau.
Chicago-referens (17:e uppl.)Não informado. Soils and Fertilizers: Abstracts of World Literature. Farnham Royal, Inglaterra: Commonwealth Agricultural Bureau, 1937.
MLA-referens (8:e uppl.)Não informado. Soils and Fertilizers: Abstracts of World Literature. Commonwealth Agricultural Bureau, 1937.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.