1. Mineralogical properties of two profiles of volcanic ash soils from Costa Rica;Andriesse;Turrialba,1973
2. Allophane determination in Ando soils by cation exchange capacity delta value;Aomine,1959
3. Quantitative determination of allophane;De Villiers;Soil Sci.,1971
4. Definitions of soils units for the soil map of the world;Dudal,1968