Official epistolography and the language(s) of power : proceedings of the first international conference of the research network imperium & officium ; comparative studies in ancient bureaucracy and officialdom, University of Vienna, 10-12 November 2010 - Procházka, Stephan, 1962-; Reinfandt, Lucian; Tost, Sven (Verlag der Österreichischen Akademie der Wissenschaften, 2015)