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The Great Mixing of Second Dominants
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"The Great Mixing of Second Dominants" by Pro Sensory licensed CC0: https://opengameart.org/content/the-great-mixing-of-second-dominants Author's attribution notice: just include my name, Alex McCulloch. Attribution appreciated but not required.
Where to put it: Game credits or video description. If the entry has a "Copyright/Attribution Notice", follow that.