Soil quality – Leaching procedures for subsequent chemical and ecotoxicological testing of soil and soil materials – Part 4: Influence of pH on leaching with initial acid/base addition (ISO/TS 21268-4:2007); German version CEN ISO/TS 21268-4:2009
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 02/01/2010
