Precise positions in the FK4 system for 120 radio source reference stars Positions are given in the FK4 system for 120 primary reference starsgrouped around the optical counterparts of 11 extragalactic radiosources. The observations were made in 1979 and 1980 with the 6-in.transit circle of the U.S. Naval Observatory. The results reported hererepresent the first step in a three-tiered process to determineastrometric positions of the optical counterparts referred to the systemof the FK4. One application of such positions is the determination of anearly inertial optical reference frame, which eventually may becompared to a reference frame at radio wavelengths.
