1. Department of Medical Physics, Azienda Ospedaliera “SS. Antonio e Biagio e C. Arrigo”, Alessandria, Italy
2. Department of Medical Physics, University Hospital “Maggiore della Carità”, Novara, Italy
3. Department of Radiotherapy, Maria Skłodowska-Curie National Research Institute of Oncology, Warsaw, Poland
4. Department of Nuclear Medicine, Azienda Ospedaliera “SS. Antonio e Biagio e C. Arrigo”, Alessandria, Italy