Links

• https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-019-7512-y

  Final published version

  Licence: CC BY: Creative Commons Attribution 4.0 International License

Text available via DOI:

• https://doi.org/10.1140/epjc/s10052-019-7512-y

  Final published version

  Available under license: CC BY: Creative Commons Attribution 4.0 International License

• https://doi.org/10.1140/epjc/s10052-019-7512-y

  Final published version