@misc{rivero1998short,
  title={A short derivation of Feynman formula},
  author={Alejandro Rivero},
  year={1998},
  eprint={quant-ph/9803035},
  archivePrefix={arXiv},
  primaryClass={quant-ph},
  url={https://arxiv.org/abs/quant-ph/9803035}
}