Discovery of gamma-ray emission from the extragalactic pulsar wind nebula N157B with H.E.S.S. - Abramowski, Attila; Zacharias, Michael; Cologna, Gabriele; Hauser, Marcus; Kaufmann, Sarah; Lenain, Jean-Philippe; Mohamed, Mahmoud; Quirrenbach, Andreas; Schwemmer, Stephanie; Wagner, Stefan (Astronomy and astrophysics, 2012)