Astrometric planet search around southern ultracool dwarfs - II. Astrometric reduction methods and a deep astrometric catalogueP. F. Lazorenko, J. Sahlmann, D. Ségransan, E. L. Martín, M. Mayor, D. Queloz and S. UdryA&A, 565 (2014) A21DOI: https://doi.org/10.1051/0004-6361/201323271
