This morning, the world learned of the death of AC/DC founder guitarist Malcolm Young at the age of 64. He had been suffering from dementia for many years. Many of his friends and admirers shared their grief on social media.

On Twitter, Eddie Van Halen wrote, "It is a sad day in rock and roll. Malcolm Young was my friend and the heart and soul of AC/DC. I had some of the best times of my life with him on our 1984 European tour. He will be missed and my deepest condolences to his family, bandmates and friends."

David Coverdale of Deep Purple and Whitesnake fame remembered him as a "great guy" and "a pleasure to know." Kiss' Paul Stanley added, The driving engine of AC/DC has died.A tragic end for a sometimes unsung icon. One of the true greats. RIP."

The list of those paying their respects to Young includes former members of AC/DC. Bassist Mark Evans, who was in the group from 1975 until 1977, simply posted a photo of Malcolm, while Dave Evans, the band's original lead singer, wrote on Facebook, "It is with sadness that I report the death of Malcolm Young, my former AC/DC bandmate and a brother founding member. May he rest in peace."

Young's fans extended far beyond the world of classic rock and metal. Country stars the Zac Brown Band called him "the heart, soul, & velvet hammer of AC/DC." Indie rockers and even comedians also recognized his greatness. Read what they had to say about him below.

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