1. Determination of molecular weight and distributions of fulvic and humic acids using flow field-flow fractionation;Beckett;Environ. Sci. & Technol.,1987
2. Molecular weight and shape of humic acid from sedimentation and diffusion measurements on fractionated extracts;Cameron;J. Soil Sci.,1972
3. Diffusion of humic acid in dilute aqueous solution;Cornel;J. Colloid Interface Sci.,1986
4. Cristian, G. D. (1994) Analytical Chemistry. John Wiley and Sons, New York, pp. 250–268
5. Dempsey, B. A. and O'Melia, C. R. (1983) Proton and calcium complexation of four fulvic acid fractions. In Aquatic and Terrestrial Humic Materials, eds. R. F. Christman and E. T. Gjessing, pp. 239–273. Ann Arbor Science, Ann Arber, MI