@Unpublished{K-theory/0852,
  author = 	 {{Viktor Petrov and Nikita Semenov}},
  title = 	 {{Higher Tits indices of algebraic groups}},
  note = 	 {{Preprint, June 22, 2007, K-theory Preprint Archives, http://www.math.uiuc.edu/K-theory/0852/}}}
}