Shindo, H. and Shojaku, M. (1999) Effect of continuous compost application on the activities of various enzymes in soil of double cropping fields. Japanese Journal of Soil Science and Plant Nutrition, in Japanese, 70, 66-69.
 Imbrahim, S.M. and Shindo, H. (1999) Effect of continu- ous compost application on water-stable soil macro- aggregation in a field subjected to double cropping. Soil Science and Plant Nutrition, 45, 1003-1007.
 Shindo, H., Hirahara, O., Yoshida, M. and Yamamoto, A. (2006) Effect of continuous compost application on humus composition and nitrogen fertility of soils in a field subjected to double cropping. Biology and Fertility of Soils, 42, 437-442. doi:10.1007/s00374-006-0088-3
 Roppongi, K., Ishigami, T. and Takeda, M. (1994) Effects of continuous application of rice straw compost on humus forms of alluvial upland soil. Japanese Journal of Soil Science and Plant Nutrition, in Japanese, 65, 426- 431.
 Aoyama, M. and Kumakura, N. (2001) Quantitative and qualitative changes of organic matter in an Ando soil induced by mineral fertilizer and cattle manure appli- cations for 20 years. Soil Science and Plant Nutrition, 47, 241-252.
 Watanabe, A., Kawasaki, S., Kitamura, S. and Yoshida, S. (2007) Temporal changes in humic acids in cultivated soils with continuous manure application. Soil Science and Plant Nutrition, 53, 535-544.doi:10.1111/j.1747-0765.2007.00170.x
 Cheshire, M.V. and Mundie, C.M. (1981) The distri- bution of labelled sugars in soil particle size fractions as a means of distinguishing plant and microbial carbo-hydrate residues. Journal of Soil Science, 32, 605-618.doi:10.1111/j.1365-2389.1981.tb01733.x
 Leinweber, P. and Reuter, G. (1992) The influence of different fertilization practices on concentrations of organic carbon and total nitrogen in particle-size fractions during 34 years of a soil formation experiment in loamy marl. Biology and Fertility of Soils, 13, 119-124.doi:10.1007/BF00337346
 Tanaka, M. and Shindo, H. (2009) Effect of continuous compost application on carbon and nitrogen contents of whole soils and their particle size fractions in a field subjected mainly to double cropping. In: Composting, Processing, Materials and Approaches, Pereira, J.C. and Bolin, J.L., Eds., Nova Science Publishers, New York, 187-197.
 Aoyama, M. (1992) Accumulated organic matter and its nitrogen mineralization in soil particle size fractions with long-term application of farmyard manure or compost. Japanese Journal of Soil Science and Plant Nutrition, in Japanese, 63, 161-168.
 Aoyama, M. and Taninai, Y. (1992) Organic matter and its mineralization in particle size and aggregate size fractions of soils with four-year application of farmyard manure. Japanese Journal of Soil Science and Plant Nutrition, in Japanese, 63, 571-580.