The Crab Nebula as a standard candle in very high-energy astrophysics Meyer, M. Horns, D. Zechlin, H.-S. 2010 - Forschungsinformationssystem der UHH
Locating the very high energy source in the Galactic Centre with milliarcsecond accuracy Abramowski, A. Gillessen, S. Horns, D. Zechlin, H.-S. 2010 - Forschungsinformationssystem der UHH