@Unpublished{K-theory/0889,
  author = 	 {{R. Hazrat and N. Vavilov}},
  title = 	 {{Bak's work on K-theory of rings (with an appendix by Max Karoubi)}},
  note = 	 {{Preprint, April 17, 2008, K-theory Preprint Archives, http://www.math.uiuc.edu/K-theory/0889/}}}
}