@techreport{EngelEtAl2009,
  author       = {Christian Engel and Andreas Roth and Peter H. Schmitt and Benjamin Wei{\ss}},
  title        = {Verification of Modifies Clauses in Dynamic Logic with Non-rigid Functions},
  number       = {2009-9},
  institution  = {Department of Computer Science, University of Karlsruhe},
  year         = {2009}
}