Weathering units and weathering catenas

Berry, 1959, Notes on Weathering Zones and Soils on Granitic Rocks in Two Tropical Regions, J. Soil Sci., 10, 54, 10.1111/j.1365-2389.1959.tb00665.x Milne, 1935, Some Suggested Units of Classification and Mapping, particularly for East African soils, Soil Res., 4, 183 Ollier, 1959, A Two-cycle Theory of Tropical Pedology, Soil Sci., 10, 137, 10.1111/j.1365-2389.1959.tb02338.x Simonson, 1960, Concept and functions of the Pedon, V.18, 127 1960