Olk, D C <br/><br/>
Environmental and Agricultural Relevance of Humic Fractions Extracted by Alkali from Soils and Natural Waters.  [electronic resource] 

 -  Journal of environmental quality  Jul 2019 
 - 1126 p.  digital 
<br/><br/> Publication Type: Journal Article 
<br/><br/><label>ISSN: </label>1537-2537 
<br/><br/><label>Standard No.: </label>10.2134/jeq2019.02.0041er  doi 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Agriculture<br/>Alkalies<br/>Humic Substances<br/>Soil