John Herndon Mercer (November 18, 1909 – June 25, 1976) was an American lyricist, songwriter, and singer, as well as a record label executive who co-founded Capitol Records with music industry businessmen Buddy DeSylva and Glenn E. Wallichs. He is best known as a Tin Pan Alley lyricist, but he also composed music and was a popular singer who recorded his own as well as others' songs from the mid-1930s through the mid-1950s. Mercer's songs were among the most successful hits of the time, including "Moon River", "Days of Wine and Roses", "Autumn Leaves", and "Hooray for Hollywood".
https://en.wikipedia.org/wiki/Johnny_Mercer