Lady Gaga isn't the only celebrity to make a major contribution towards Hurricane Sandy relief efforts.

Justin Bieber and Rihanna are also stepping up with major donations that will go directly towards hurricane victims in NYC and New Jersey. Justin is teaming up with charity Pencils of Promise to donate a dollar to relief efforts for every ticket sold at his two shows in Madison Square Garden, show in New Jersey and show in Brooklyn. Since all four concerts already sold out, that means he'll be writing a check for $79,000! "We decided that for the Jersey, Brooklyn, and 2 MSG shows every ticket sold a dollar will be donated to Hurricane Sandy Relief #GIVEBACK." he tweeted. "And all 4 shows are SOLD OUT so U are all helping us make a difference in the lives of those that need it right now."

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While Justin is going for the cash, Rihanna is focusing on the supplies and basic necessities that many people lack after the Hurricane. She is donating 1,000 sleeping bags through the New York Daily News and is hoping to get more goods during her listening party at Jay-Z's 40/40 club tonight in NYC. In order to be admitted in to listen to her new album Unapologetic, fans are being asked to bring supplies such as diapers, coats and blankets.

What do you think of Justin and Rihanna's generosity?

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