How Did Robert Penn Warren Die?

Robert Penn Warren was an American poet, novelist, literary critic and professor at Yale University. He was one of the founders of New Criticism. He was also a charter member of the Fellowship of Southern Writers. He founded the literary journal The Southern Review with Cleanth Brooks in 1935. He received the 1947 Pulitzer Prize for the Novel for All the King's Men (1946) and the Pulitzer Prize for Poetry in 1958 and 1979.