@article{alet2005directed,
  author = {Alet, F. and Wessel, S. and Troyer, M.},
  title = {{Generalized Directed Loop Method for Quantum Monte Carlo Simulations}},
  journal = {Physical Review E},
  volume = {71},
  number = {3},
  pages = {036706},
  year = {2005},
  doi = {10.1103/PhysRevE.71.036706}
}