DIN 19682-13
DIN 19682-13 Soil quality - Field tests - Part 13: Determination of carbonate, sulfide, pH-value and iron(II)-ions
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 01/01/2009
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 01/01/2009