This picture from the American Memory Project of the Library of Congress shows conductor Serge Koussevitzky with his Boston Symphony Orchestra in 1949. In 1945 the Koussevitzky Foundation commissioned an orchestral work from Villa-Lobos, which became the symphonic poem Madona. Villa dedicated the work to Koussevitzky's wife Natalie.
Madona is a work that I had never heard until today, when I visited the excellent Brazilian Concert Music blog. An ancient (I would guess 1950s vintage) off-the-air broadcast of the work from Belgium made its way to the collection of the Brazilian composer Harry Crowl, and then on to the blog. This sounds like a shortwave broadcast; it's complete with Morse code interference.
Perhaps it came from ORU, The International Goodwill Station, and was recorded in Brazil. The romance of Shortwave Listening in the olden days! The QSL above is from the Committee to Preserve Radio Verification at the Library of American Broadcasting.
In any case, I urge you to listen to this work, written in the same year as Bachianas Brasileiras #9 and the String Trio. I'm hoping it's not too long before we hear about new performances of Madona (or even new recordings), since it's one of the scores included in the new Villa-Lobos Digital Project of the ABM.