1. Ecole Polytechnique Fédérale de Lausanne (EPFL), Biomolecular Mass Spectrometry Laboratory, Institute of Chemistry and Chemical Engineering, 1015, Lausanne, Switzerland
2. Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, USA
3. Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, USA
4. Ion Physics Laboratory, Radiophysics Faculty, State Polytechnical University, Saint-Petersburg, Russia