THREE.JS R149
Source: https://github.com/mrdoob/three.js/tree/r149

The MIT License

Copyright © 2010-2023 three.js authors

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
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furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
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TERRAIN
Federal Office of Topography swisstopo, swissALTI3D.
Mapzen / Tilezen, Copernicus EU-DEM / USGS.
Source and attribution: https://github.com/tilezen/joerd/blob/master/docs/attribution.md
Detailed terrain provenance and hashes are in work/TERRAIN_PROVENANCE.json and work/ALPINE_RING_PROVENANCE.json in the authoring workspace.
Surface materials, snow, lighting, stars and clouds are artistic.
Background music: the Proteryx3D soundtrack, reused with the project owner's authorization; distributed locally as assets/proteryx-ambience.opus.

swisstopo data terms: https://www.swisstopo.admin.ch/en/terms-of-use-free-geodata-and-geoservices