To cite osmdata in publications use:

Padgham M, Rudis B, Lovelace R, Salmon M (2017). “osmdata.” The Journal of Open Source Software, 2(14). doi: 10.21105/joss.00305, https://doi.org/10.21105/joss.00305.

Corresponding BibTeX entry:

  @Article{,
    title = {osmdata},
    author = {Mark Padgham and Bob Rudis and Robin Lovelace and Maëlle
      Salmon},
    journal = {The Journal of Open Source Software},
    year = {2017},
    volume = {2},
    number = {14},
    month = {jun},
    publisher = {The Open Journal},
    url = {https://doi.org/10.21105/joss.00305},
    doi = {10.21105/joss.00305},
  }