@techreport{hoefler-topocolls-mpi3,
  author={Torsten Hoefler and F. Lorenzen and D. Gregor and Andrew Lumsdaine},
  title={{Topological Collectives for MPI-2}},
  institution={Open Systems Lab, Indiana University},
  year={2008},
  month={Feb.},
  pages={},
  volume={},
  number={},
  booktitle={},
  location={},
  publisher={MPI Forum},
  issn={},
  isbn={},
}