OpenGameArt.org
Dreamless Sleep
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"Dreamless Sleep" by Jan125 licensed CC-BY 4.0: https://opengameart.org/content/dreamless-sleep Author's attribution notice: I like having a humanly readable format. Please save in .mmp instead of .mmpz or be insulted. For info, see project file.
Where to put it: Game credits or video description. If the entry has a "Copyright/Attribution Notice", follow that.