Security in Transnational Interoperable PPDR Communications: Threats, Requirements and Architecture Solution. - Ramon Ferrús; Oriol Sallent; Cor Verkoelen; Frank Fransen; Keld Andersen; Christian Bjerrum-Niese; Jaakko Saijonmaa; Claudia Olivieri; Michel Duits; Anita Galin; Franco Pangallo; Debora Proietti Modi (Int. J. Distributed Syst. Technol., 2016)