@article{smith_1856, 
  title={A Course of Lectures ON THE THEORY AND PRACTICE OF OBSTETRICS.}, 
  volume={68}, 
  DOI={10.1016/s0140-6736(02)60518-5}, 
  number={1738}, 
  publisher={Elsevier BV}, 
  author={Smith}, 
  year={1856}
  }