Harry Mackenzie is a resident of Glasgow, Scotland who has researched and written extensively on radio during the 1940s. His collection consists of an unpublished 1992 manuscript, The Johnny Mercer Chesterfield Music Shop, a revision of the discography he published in 1986.

The Johnny Mercer Radio Programs Collection consists of audio recordings of more than 250 radio broadcasts, primarily dated 1934-1956. These musical radio shows feature performances from many notable entertainers of the time, but they all include either performances by Johnny Mercer, performances of his songs, or are otherwise related to his career.