To cite echor in publications use:

Schramm M (2020). echor: Access EPA 'ECHO' Data. doi: 10.5281/zenodo.3635017, https://CRAN.R-project.org/package=echor.

Corresponding BibTeX entry:

  @Manual{,
    title = {{echor}: Access EPA 'ECHO' Data},
    author = {Michael Schramm},
    year = {2020},
    url = {https://CRAN.R-project.org/package=echor},
    doi = {10.5281/zenodo.3635017},
  }