1. Centre for Preventive Doping Research/Institute of Biochemistry; German Sport University Cologne; Germany
2. Centre for Education and Science of the Federal Revenue Administration; Cologne; Germany
3. Autoridade Antidopagem de Portugal; Av. Prof. Egas Moniz (Estádio Universitário); 1600-190; Lisboa; Portugal
4. Biological Medical Research Center; Heinrich-Heine-University of Düsseldorf, Moorenstrasse 5; 40225 Düsseldorf; 1600-190; Germany