It was really hard to find, but here are the dates for John Clements, who composed "Flower of Beauty" and "There is Sweet Music."
(b. 1910 - d. 1986)
Thanks to John Helgen, who provided me with the source. You can check it on the British Music Information Centre website. The database MUSICA appears to be wrong, listing the dates for John Clements, actor, who was born in the same year.