Conversation so far:
Who was Johnny Cash's first wife?
Johnny Cash's first wife was Vivian Liberto.
Where did Johnny Cash and his first wife, Vivian Liberto meet?
Johnny Cash met 17-year-old Italian-American Vivian Liberto at a roller skating rink in her native San Antonio

Question: Where did they meet
Self-contained rewrite: Where did Johnny Cash and Vivian Liberto meet?