@unpublished{Schulze2009,
  author  = {Bert-Wolfgang Schulze},
  title   = {On a paper of Krupchyk, Tarkhanov, and Tuomela},
  institution = {Institut f{\"u}r Mathematik},
  series    = {Preprint},
  number    = {(2008) 05},
  year    = {2009},
}