4) Matsuo, S. and Nishida, K. (1968): "Physical and chemical properties of decomposed granite soil grains," Soils and Foundations, Vol. 8, No. 4, pp. 10-20.
5) Matsuo, S. and Nishida, K. (1970): "The properties of decomposed granite soils and their influence on permeability," Soils and Foundations, Vol. 10, No. 1, pp. 93-105.