Reference

Jose Ignacio Canudo, Penelope Cruzado-Caballero, Miguel Moreno-Azanza (2005): Possible theropod predation evidence in hadrosaurid dinosaurs from the Upper Maastrichtian (Upper Cretaceous) of Arén (Huesca, Spain) – Kaupia - Darmstädter Beiträge zur Naturgeschichte – 14: 9 - 14.