Polak, M. 2009, The Roman military presence in the Rhine delta in the period c. AD 40 – 140. In: A. Morillo, N. Hanel & E. Martín (eds), Limes XX, XXth International Congress of Roman Frontiers studies, Leon, (España), Septiembre 2006, Madrid (Anejos de Gladius, 13-2), 945-953.