Hopp, U. Optical and Interpretative Astronomy, MPI for Extraterrestrial Physics, Max Planck Society;
Hopp, U., Schulte-Ladbeck, R. E., & Kerp, J. (2007). Searching for stars in compact high-velocity clouds – II. Monthly Notices of the Royal Astronomical Society, 374(3), 1164-1168. doi:10.1111/j.1365-2966.2006.11236.x.