Jm. Paredes et al., OPTICAL COUNTERPART OF GALACTIC PLANE VARIABLE RADIO-SOURCES, Astronomy & Astrophysics. Supplement series, 102(2), 1993, pp. 381-387
We present I-band deep CCD exposures of the fields of galactic plane r
adio variables. An optical counterpart, based on positional coincidenc
e, has been found for 15 of the 27 observed program objects. The Johns
on I magnitude of the sources identified is in the range 18-21.