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BBC Scotland Science Correspondent
Some of Stephen Hawking's personal items, including a signed copy of his 1965 PhD thesis, have raised more than £1.8m ($2.35m) at auction.
A total of 22 items owned by the Cambridge physicist, who died in March, were auctioned by Christie's.
The copy of his thesis titled Properties of Expanding Universes - one of only five - was sold for £584,750.
An early wheelchair raised £296,750 for charity and a script for his appearance on The Simpsons sold for £6,250.
Lucy Hawking speaks to the BBC's Luke Jones about losing her father earlier this year and his new book which she has helped finish.