Influence of the Treatment Process on Nitrogen Content in Humic Acids Extracted from Sewage Sludge
J. Polak, W. W. Sulkowski
Department of Environmental Chemistry and Technology, Institute of Chemistry,
University of Silesia,
Szkolna 9, 40-006 Katowice, Poland
Pol. J. Environ. Stud. 2006;15(4):573–577