Original sentence: The Blue Sky Boys were an American country music duo consisting of the brothers Earl Bolick (born November 16, 1919 - died April 19, 1998) and Bill Bolick (born October 28, 1917 - died March 13, 2008), whose careers spanned over forty years
Edited sentence: The Blue Sky Boys were an American country music duo consisting of the brothers Earl Bolick (November 16, 1919 – April 19, 1998) and Bill Bolick (October 28, 1917 – March 13, 2008), whose careers spanned over forty years