Question: Which lead vocalist wrote songs for Black Sabbath?
Related documents: [0]  [DOC] "The Mob Rules" is a song by British rock band Black Sabbath from their 1981 album, "Mob Rules". The song was written by Ronnie James Dio and Tony Iommi. The song also released as the first single from the album. [END] 
[1]  [DOC] Mob Rules is the tenth studio album by English rock band Black Sabbath, released in November 1981. It followed 1980's "Heaven and Hell", and it was the second and last Black Sabbath studio album to feature lead vocalist Ronnie James Dio prior to the 1992 album "Dehumanizer". [END] 
Answer: 
Ronnie James Dio
Ronnie James Dio