ABBA celebrated the 50th anniversary of their founding by performing onstage together for the first time in 30 years.
Agnetha Faltskog, Björn Ulvaeus, Benny Andersson and Anni-Frid (Frida) Lyngstad were all in attendance at Stockholm’s Berns Salonger Sunday for a private gala honoring the influential pop group, and while the quartet stood…