@Unpublished{K-theory/0504,
  author = 	 {{J.F. Jardine}},
  title = 	 {{Presheaves of chain complexes}},
  note = 	 {{Preprint, July 19, 2001, K-theory Preprint Archives, http://www.math.uiuc.edu/K-theory/0504/}}}
}