Most of the files are

  :Copyright: This stylesheet has been placed in the public domain.
  Copyright  2018 Forest and Biomass Romania
  Copyright 2016 Camptocamp SA
  Copyright 2016 Camptocamp SA, Onestein B.V.
  Copyright 2017 ACSONE SA/NV
  Copyright 2017 Akretion - Alexis de Lattre
  Copyright 2017 Eficent Business and IT Consulting Services, S.L.
  Copyright 2018 Camptocamp SA
  Copyright 2018 Eficent Business and IT Consuting Services, S.L.
  Copyright 2019 ACSONE SA/NV (<http://acsone.eu>)
  © 2016 Damien Crier (Camptocamp)
  © 2018 Forest and Biomass Romania SA
  Copyright 2018 Flectra Community

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parties. In this case the original copyright of
the contributions can be traced through the
history of the source version control system.

When that is not the case, the files contain a prominent
notice stating the original copyright and applicable
license, or come with their own dedicated COPYRIGHT
and/or LICENSE file.