@article{freedson1998,
  title={Calibration of the Computer Science and Applications, Inc. accelerometer},
  author={Patty S. Freedson and Edward L. Melanson and John R. Sirard},
  year={1998},
  journal={Medicine & Science in Sports & Exercise},
  doi={10.1097/00005768-199805000-00021},
  url={https://doi.org/10.1097/00005768-199805000-00021}
}