@article{blum,
  author  = {L. C. Blum and J.-L. Reymond},
  title   = {970 Million Druglike Small Molecules for Virtual Screening in the Chemical Universe Database {GDB-13}},
  journal = "J. Am. Chem. Soc.",
  volume  = 131,
  pages   = 8732,
  year    = 2009
}