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The training of the Russian Archers
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"The training of the Russian Archers" by Dogers licensed CC-BY-SA 4.0: https://opengameart.org/content/the-training-of-the-russian-archers Author's attribution notice: This work is licensed under CC-BY-SA 4.0.
Where to put it: Game credits or video description. If the entry has a "Copyright/Attribution Notice", follow that.