Optical astrometric positions of 59 northern ICRF radio sourcesM. Assafin, D. A. Nedelcu, O. Badescu, P. Popescu, A. H. Andrei, J. I. B. Camargo, D. N. da Silva Neto and R. Vieira MartinsA&A, 476 2 (2007) 989-993DOI: https://doi.org/10.1051/0004-6361:20078441
