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In page Wave (audience):

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Krazy George Henderson perfected the wave at National Hockey League games, followed later by the earliest available video documentation of a wave, which he led on October 15, 1981, at a Major League Baseball game in Oakland, California.[3][4][5][6][7][8] This wave was broadcast on TV, and George has used a videotape of the event to bolster his claim as the inventor of the wave.[3][4] On October 31, 1981, a wave was created at a University of Washington football game against Stanford at Husky Stadium in Seattle, and the cheer continued to appear during the rest of that year's football season.[6] Although the people who created the first wave in Seattle have acknowledged Henderson's wave at a baseball stadium, they claimed to have popularized the phenomenon.[citation needed]