@misc{10134,
  author = {J. Hardy and T. Holford and G. Hall and M. Bracken},
  title = {Strategies for identifying pregnancies in the automated medical records of the General Practice Research Database},
  year = {2004},
  journal = {Pharmacoepidemiol Drug Saf},
  volume = {13},
  number = {11},
  pages = {749-59},
  issn = {1053-8569 (Print) 1053-8569},
  doi = {10.1002/pds.935},
}