1. Mass Spectrometry, National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj-Napoca, Romania
2. ICSI Analytics, National Research and Development Institute of Cryogenics and Isotopic Technologies, Ramnicu Valcea, Romania
3. National Research Institute for Cryogenics and Isotopic Technologies, Ramnicu Valcea, Romania
4. Faculty of Environmental Science and Engineering, Research Department, Babeș-Bolyai University, Cluj-Napoca, Romania
5. Research Department, National Research and Development Institute for Forestry "Marin Drăcea" Calea Bucovinei, Câmpulung Moldovenesc, Romania