@article{ref1,
  author = "S. M. O'Brien and J. P. Jacobs and D. R. Clarke and B. Maruszewski and M. L. Jacobs and W. I.  H. L. and C. I. Tchervenkov and K. F. Welke and Z. Tobota and G. Stellin and C. Mavroudis and J. L. Hamilton and J. W. Gaynor and M. Pozzi and F. G. Lacour-Gayet",
  title = "Accuracy of the Aristotle Basic Complexity Score for Classifying the Mortality and Morbidity Potential of Congenital Heart Surgery Operations",
  year = 2007,
  journal = "The Annals of Thoracic Surgery",
  publisher = "Elsevier",
  volume = 84,
  number = 6,
  pages = "2027-2037",
  month = "Dec",
  doi = "10.1016/j.athoracsur.2007.06.031",
  url = "http://dx.doi.org/10.1016/j.athoracsur.2007.06.031"
}