[The first-derivative sinus node electrogram (FDSNE)].

@article{Wu1987TheFS,
  title={[The first-derivative sinus node electrogram (FDSNE)].},
  author={Hong Yan Wu and Fa-long Gu},
  journal={Zhonghua xin xue guan bing za zhi},
  year={1987},
  volume={15 3},
  pages={148-9, 191}
}