Question: Which song that won four 1968 Grammy Awards was written by a musician known for his mastery of the fiddle and banjo?
Sentence (from "John Hartford"): John Cowan Hartford (December 30, 1937 – June 4, 2001) was an American folk, country and bluegrass composer and musician known for his mastery of the fiddle and banjo, as well as for his witty lyrics, unique vocal style, and extensive knowledge of Mississippi River lore.
Relevant evidence: Yes