Letrozole: updated duration of response.

@article{Chaudri1999LetrozoleUD,
  title={Letrozole: updated duration of response.},
  author={H A Chaudri and Patrick Trunet},
  journal={Journal of clinical oncology : official journal of the American Society of Clinical Oncology},
  year={1999},
  volume={17 12},
  pages={3856-60}
}