2 correct some rankings and add more info
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Ritchie Valens' "La Bamba" was the B-side of "Donna". While both peaked separately atDonna reached #2 and "La Bamba" only #22 on Billboard Hot 100, I think "La Bamba" could be considered "more popular" in the long term. Valens was credited with a #1 hit when the Los Lobos version reached #1. Also "La Bamba" ranked No. 98 in VH1's 100 Greatest Songs of Rock and Roll in 1999. 

However, I don't think "Donna" was "almost forgotten".

Ritchie Valens' "La Bamba" was the B-side of "Donna". While both peaked separately at #2, I think "La Bamba" could be considered "more popular". However, I don't think "Donna" was "almost forgotten".

Ritchie Valens' "La Bamba" was the B-side of "Donna". While Donna reached #2 and "La Bamba" only #22 on Billboard Hot 100, I think "La Bamba" could be considered "more popular" in the long term. Valens was credited with a #1 hit when the Los Lobos version reached #1. Also "La Bamba" ranked No. 98 in VH1's 100 Greatest Songs of Rock and Roll in 1999. 

However, I don't think "Donna" was "almost forgotten".

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Ritchie Valens' "La Bamba" was the B-side of "Donna". While both peaked separately at #2, I think "La Bamba" could be considered "more popular". However, I don't think "Donna" was "almost forgotten".