@article{dickman_vidigal_2003,  title={Path integrals and perturbation theory for stochastic processes},  volume={33},  ISSN={0103-9733},  url={https://doi.org/10.1590/S0103-97332003000100005},  DOI={10.1590/S0103-97332003000100005},  number={1},  journal={Brazilian Journal of Physics},  publisher={Sociedade Brasileira de Física},  author={Dickman, Ronald and Vidigal, Ronaldo},  year={2003},  month={Mar},  pages={73–93} }