A rare Harry Potter first edition which was used by a father to help his children learn English is set to fetch up to £30,000 at auction.
The copy of Harry Potter and the Philosopher's Stone had been on a bookshelf for 21 years and is one of only 500 hardcover first editions of the novel.
It was purchased by a retired British expat, who lives in Luxembourg.
He plans to use money from the sale to pay off his daughter's student loans.
The vendor, who wants to remain anonymous, said he had bought the book for his children about 18 months after it was first published.
"I needed English books to read to my three children at bedtime as I was on a mission to teach them my native language from an early age," he said.
"Their mother is Luxembourgish and they were going to state schools here in Luxembourg, so I needed to make a bit of an effort."
After deciding to re-read the series a few months ago, he realised it was a first edition, as it has a duplication of '1 wand' on page 53 and an issue number of "10 9 8 7 6 5 4 3 2 1".
The seller posted the book to Hansons Auctioneers, in Staffordshire, wrapped in a tea towel.
The novel will go under the hammer on 13 October.
Hansons Auctioneers books expert Jim Spencer said: "True first issues are seriously scarce.
"Only 500 were printed, 300 of which were sent to schools and libraries. This is extra rare because it's one of the remaining 200."