@Unpublished{K-theory/0232,
  author = 	 {{Winfried Bruns and Joseph Gubeladze}},
  title = 	 {{Polyhedral algebras, arrangements of toric varieties, and their groups}},
  note = 	 {{Preprint, November 7, 1997, K-theory Preprint Archives, http://www.math.uiuc.edu/K-theory/0232/}}}
}