@article{DimitrievSaposhnikovGoesseletal.1997,
  author    = {Dimitriev, Alexej and Saposhnikov, Vl. V. and G{\"o}ssel, Michael and Saposhnikov, V. V.},
  title     = {On-line testing by self-dual duplication},
  year      = {1997},
  language  = {en}
}
@article{DimitrievSaposhnikovGoesseletal.1997,
  author    = {Dimitriev, Alexej and Saposhnikov, Vl. V. and G{\"o}ssel, Michael and Saposhnikov, V. V.},
  title     = {Self-dual duplication - a new method for on-line testing},
  year      = {1997},
  language  = {en}
}