1. SP Technical Research Institute of Sweden, Chemistry and Materials Technology,
Borås, Sweden
2. Siemens, Gothenburg, Sweden
3. Physikalisch-Technische Bundesanstalt, Metrologie in der Chemie,
Braunschweig, Germany
4. Clinical Chemistry, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, and Department of Clinical Chemistry, County Council of Östergötland,
Linköping, Sweden