Analysis of a Sample of RC Catalog Objects in the Region Overlapping
  with the Areas Covered by FIRST and SDSS Surveys. II: Optical Identification
  with the SDSS Survey and USNO-B1 and 2MASS Catalogs
  We report the results of optical identification of a sample of RC catalog
radio sources with the FIRST and SDSS surveys. For 320 sources identified with
NVSS and FIRST objects we perform optical identification with the SDSS survey.
When selecting optical candidates we make maximum use of the information about
the structure of radio sources as provided by the FIRST survey images. We find
optical candidates for about 80% of all radio sources.
