SIMBAD references

Redshift distributions of extragalactic objects have been suggested to exhibit periodicities. But based on which periodicities are claimed, peaks and troughs have been shown to be artifacts of observational and analytical selection effects. The long debate over the matter has so far been concerned mostly with quasi-stellar objects (QSOs). However, the claim for periodicities has now been extended to gamma-ray bursts (GRBs), another species of extragalactic objects with high redshifts. The redshift distribution of the 33 objects (23 GRBs and associated nine QSOs and one active galaxy) for which a periodicity is claimed (Burbidge), with one new GRB redshift added and one too many QSO redshift eliminated, is compared with distributions of three selection effect parameters. It is shown that the peaks and troughs in the redshift distribution of the 33 objects have appeared as a result of observational and analytical selection effects. This leads to the conclusion that there is no periodicity in the distribution.