Attribution 4.0 International (CC BY 4.0)

Data of the sources marked CC-BY-4.0 in LICENSES.md is licensed under the
Creative Commons Attribution 4.0 International (CC BY 4.0) licence. The full legal code is at:

  https://creativecommons.org/licenses/by/4.0/legalcode

and its summary at:

  https://creativecommons.org/licenses/by/4.0/

Attribution: the author, home page and address of each source are in
LICENSES.md (table "Sources"). The lists were changed: the domains were
normalized, deduplicated, merged with other sources and filtered.
