As U.S. Democrats and Republicans continue to grapple with passing (or not passing, as the news has revealed) new gun-control measures in the wake of this month's wave of shooting deaths in Orlando, Billboard has written a pro-gun control "Open Letter to Congress" featuring a slew of signatures from established artists in the music industry. Among the many, many names: Katy Perry, Meghan Trainor, Calvin Harris, Jennifer Lopez, Cher, Joe Jonas, Kesha, Barbra Streisand, Common, Diplo, Alicia Keys, Sia, Paul McCartney, Ringo Starr, Iggy Pop, Pearl Jam, Yoko Ono, ?uestlove, Bonnie Raitt, Lin-Manuel Miranda, Billy Joel, Shakira, Britney Spears, Christina Aguilera, Dixie Chicks, DJ Khaled, and more. Billboard writes: Like the rest of the country and the world, Billboard editors were horrified by the mass killing at Orlando’s Pulse nightclub on June 12, and by the murder of singer Christina Grimmie the night before. Both tragedies occurred where musicians and music fans gathered. And so faced with another gun-related tragedy, the staff organized this special “Open Letter to Congress” cover of Billboard. With the help of leading gun-violence prevention group Everytown for Gun Safety, editors reached out to those we cover in the music industry, and asked for their support and their signatures to help seek a sane and safe end to gun violence. Within minutes, Joan Jett was the first to sign on. Lady Gaga shortly followed. Within hours, and then in a matter of just a few days, nearly 200 top artists and executives — pop stars (including Grimmie's friend Selena Gomez), rappers, rock gods, legends, Broadway heroes, even two Beatles and Yoko Ono — lent their voices to the chorus of Americans looking to our political leaders for change. Billboard, artists and music-industry executives join so many members of the House and Senate this week proudly advocating for common-sense gun safety. View the letter — signatures and all — in its entirety here.