Extragalactic Radio Sources: Accurate Positions from Very-Long Interferometry Observations

Relative positions for 12 extragalactic radio sources have been determined via wide-band verylong-baseline interferometry (A 3.8 cm). The standard error, based on consistency between results from widely separated periods of observation, appears to be no more than 0'!1 for each coordinate of the seven sources that were well observed during two or more periods. The uncertainties in the coordinates determined for the other five sources are larger, but in no case exceed 0'!5. Subject heading: radio sources