1. Genesis and hardening of laterite in soils;Alexander;USDA Tech. Bull. 1282,1962
2. Iron oxide removal from soils and clays;Aguilera,1953
3. Stability of iron oxides in two contrasting soils with contrasting colors;Bigham;Soil Sci. Soc. Am. J.,1991
4. Genetic evaluation of the profile distribution of aluminum, iron and manganese oxides;Blume,1969
5. Soil classification as used in Brazilian soil surveys;Camargo,1986