Somchai Anusontpornperm, Stephen Nortcliff, and Irb Kheoruenromne, “Interpretability Comparison between Soil Taxonomic and Fertility Capability Classification Units: A Case of Some Major Cassava Soils in Northeast Thailand”, Agr. Nat. Resour., vol. 43, no. 5, pp. 9–18, Dec. 2009.