_which_ National Philharmonic Orchestra is this?
Every evidence it is Great Britain, AKA NPO, London. USA Library of Congress has more on these connections:
Library of Congress
The National Philharmonic Orchestra was a British orchestra created exclusively for recording purposes. It was founded by RCA producer Charles Gerhardt and orchestra leader / contractor Sidney Sax due in part to the requirements of the Reader's DigestContinue reading at Wikipedia...
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