1. Center for Preventive Doping Research—Institute of Biochemistry, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany
2. Westfälische Wilhelms-Universität Münster, Institute of Inorganic and Analytical Chemistry, Corrensstr. 30, 48149 Münster, Germany
3. Bayer CropScience AG, Alfred-Nobel-Str. 50, 40789 Monheim, Germany