2  "Covent Garden Operas" - Magic Flute and La Traviata 

As follows: 

Magic Flute ( Mozart )

by Rupert Lee

published by Boosey & Hawkes, London, 1947

Green card covers. Light foxing to inside cover else good. Covent Garden Operas. First published in April 1947 to correspond with the production of The Magic flute by the Covent Garden Opera. 35 pages.

La Traviata ( Verdi )

by Trevor Fisher

published by Boosey & Hawkes, London, 1948

31 pages containing Black and white illustrations. "Covent Garden Operas" series.