Identification number of the source in the Fourth Cambridge Radio Survey Catalogue (4C):
Optical name for the identification:
Code for confirmation or invalidation of the identification:
subsequent spectrum showed that proposed identification is a star
subsequent spectrum showed that proposed identification is really a QSO (quasar)
identification was discarded on the basis of a better radio or optical position
identification was confirmed by means of accurate radio and optical positions; or, in the case of a quasar, by measuring its UBV color photoelectrically
proposed identification was discarded and the field shown to be empty, or the preceding classification as an empty field was confirmed
proposed identification was discarded and the field shown to be obscured