After recording a set of 11 album sets of instrumental symphonic classical music for Music Appreciation Products, Inc. for their initial "World's Greatest Music" series between 1938-1940, RCA Victor recording engineers also facilitated the initial "World's Famous Operas" series recorded in 1940 (12 album sets in total). The artists were not explicitly credited on the original releases; however, recording session records have been found that identify who they were. Further information about the vocalists, conductor, and orchestra employed in these recording sessions made in 1940 can be found here: https://78records.wordpress.com/2017/10/11/new-%e2%80%a2-the-worlds-greatest-operas-discography-rca-victor-series-by-john-bolig.
The original album set came with an appreciation booklet giving background information on the composer, the work itself, and a lyrics sheet (with English translations). These can be viewed here: https://www.discogs.com/release/9521602-Samuel-Chotzinoff-Madama-Butterfly-An-Appreciation-By-Samuel-Chotzinoff/image/SW1hZ2U6MjYxMzYwNDc=.
