Watching Behind Enemy Lines and It Looks Like Niko Makes A Cameo : r/GTA

Voiced Actor (Niko Bellic) addon - S.T.A.L.K.E.R. Anomaly mod for S.T.A.L.K.E.R.: Call of Pripyat - ModDB

Niko Bellic, Neo Encyclopedia Wiki

Niko Bellic, GTA Wiki

Niko Bellic Actor got paid $100,000 for Grand Theft Auto IV

GTA IV's Niko and Roman Bellic Actors Call Foul Play

Karen Daniels, GTA Wiki

Niko Bellic - Saints Row: The Third

Voicebox 360 The New Yorker

I really hope niko make an appearance in GTA VI, I'm not sure how they'll implant it, but it'll be cool for the nostalgia : r/GTA

Grand Theft Auto IV: the blockbuster game that dared to be truly political