1. Chen, J. S., He, D. W., etal.: 2003, ‘Can the COD values truly reflect the water pollution of the Yellow River?’, Environ. Chem. 22(6), 611–614, (in Chinese).
2. Chen, J. S., Zhang, Y., Yu, T. and He, D. W.: 2004, ‘Dissolubility and degradability of organic matters in sediment of the Yellow River’, Acta Scientiae Circumstantiae 24(1), 1–5 (in Chinese).
3. Chen, J. S., Zhang, Y. and Yu, T.: 2004, ‘Influence of the suspended sediments on the water quality parameters CODCr, CODMn and BOD5 in the Yellow River, China’, Acta Scientiae Circumstantiae 24(3), 369–375 (in Chinese).
4. Chapman, D.: 1992, Water Quality Assessments, Chapman & Hall, London, New York, Tokyo, Melbourne, Madras, 585 pp.
5. Chinese Soil Association, the Special Committee on Chemical Analysis of Agricultural Soil: 1974, Conventional Analytical Methods for Soil, Beijing, The Scientific Press (in Chinese).