Differential viral fitness between H1N1 and H3N8 avian influenza viruses isolated from mallards (Anas platyrhynchos) - Ferreira, Helena Lage; Vangeluwe, Didier; Van Borm, Steven; Poncin, Olivier; Dumont, Nathalie; Ozhelvaci, Orkun; Munir, Muhammad; Berg, Thierry van den; Lambrecht, Bénédicte (Avian Diseases, 2015)