This artist uses a different band name for each album released (g//z/r: Plastic Planet (1995), geezer: Black Science (1997), GZR: Ohmwork (2005)), and used yet another one in its first, short-lived, version: Geezer Butler Band. The current official page http://www.geezerbutler.com/gzr.html is promoting the latest album, Ohmwork, and obviously focuses on the latest name (GZR).