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Ian Gavan/Getty Images, Todd Williamson/WireImage
These two music legends just don't know when to quit. While Gaga has cited Madge as a huge inspiration, Madonna has often accused Lady G of copycatting her music and even called her hit song "Born This Way" a "bit reductive." The "Judas" singer fired back of course, poking fun at the pop star, but considering both singers' penchant for eyebrow-raising antics, we have a feeling there's only more to come.
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