Image caption Louis Armstrong was a Desert Island Discs castaway in 1968

Louis Armstrong's personal copy of his appearance on BBC Radio 4's Desert Island Discs is among the recordings to be added to the show's online archive.

The Armstrong edition was tracked down by the production team after a listener alerted them to the existence of a recording of the show in the US.

Other rescued recordings feature author Reverend W Awdry, Dame Diana Rigg and Doctor Who star William Hartnell.

It is the first time the editions have been heard in more than 45 years.

All the subjects were interviewed between 1964 and 1970 by Roy Plomley, with Thomas the Tank Engine author Awdry's 1964 appearance being the earliest.

Only part of the Hartnell interview, recorded in 1965, has been recovered.

Awdry, Hartnell and Dame Diana were all personal audio recordings donated by listeners and have been carefully restored for the archive.

The Rigg edition, first broadcast in 1970, had been saved on an old quarter inch tape.

The Armstrong edition, which was gifted to him by the BBC after he recorded the programme in 1968, was donated courtesy of the research collections of the Louis Armstrong House Museum.

'Frisky'

"Louis Armstrong's appearance on Desert Island Discs is the next best thing to hanging out with the legendary trumpeter," said Ricky Riccardi, archivist for the museum.

"Armstrong's in a frisky, quick-witted mood throughout the broadcast, tells some of his favourite stories about his rough upbringing in New Orleans and spins some good music - namely because he chooses so much of his own!"

Armstrong's favourite piece was his own track, Blueberry Hill. He also chose to take his own autobiography, while his luxury item - predictably enough - was a trumpet.

Image copyright Getty Images Image caption Diana Rigg pictured at home in 1970 with her pet parrot Chrome

Dame Diana chose a vegetable garden as her luxury item, Hartnell took cigarettes, and Rev Awdry took writing materials. Among his track choices was train sound effects.

The Desert Discs online archive was launched in 2011, in a bid to collate all the recordings from the show's 73-year-history.

Current host Kirsty Young described it as "a broadcasting treasure trove".

"Unearthing yet more recordings and adding them to our archive is great news, not just for the much-valued listeners we have now, but for listeners of the future too," she added.

Listen to Louis Armstrong's Desert Island Discs programme, and other items from the Desert Island Discs archives.