@article{adams_o'brien_2002, 
  title={Unknown Primary Squamous Cell Carcinoma of the Head and Neck: A Review of Diagnosis, Treatment and Outcomes}, 
  volume={25}, 
  DOI={10.1016/s1015-9584(09)60172-x}, 
  publisher={Elsevier BV}, 
  author={Adams and O'Brien}, 
  year={2002}
  }