1. The Humic Acids, Studies in Their Chemistry, Physics, and Soil Science;Oden;Kolloidchemishe Beihefte,1919
2. Biopolymer-Metal Complex Systems. II. Physical Properties of Humic Substances and Their Metal Complexes;Sipos;Acta Agronomic Acad. Scient. Hung.,1978
3. The Analytical Concentration of Humic Substances From Natural Waters;Mantoura;Anal. Chim. Acta,1975