2 of 17:
Barbra Streisand, who sang the 1979 song 'No More Tears (Enough Is Enough)' with Donna Summer, said in a statement after the disco queen's death: 'I was shocked to hear about Donna. She was so vital the last time I saw her a few months ago. I loved doing the duet with her. She had an amazing voice and was so talented. .. It's so sad.'
(Pictured: Barbra Streisand appears on the cover of her 2011 album 'What Matters Most.')
(Columbia Records / Casablanca)