Conversation so far:
Who wrote the song Hound Dog?
Hound Dog is a twelve-bar blues song written by Jerry Leiber and Mike Stoller.
On what side of the record was the song Hound Dog?
Elvis Presley's 1956 Hound Dog was released as the B-side to the single Don't Be Cruel.

Question: What year was this
Self-contained rewrite: In what year was Elvis Presley's Hound Dog released?