An 80-page handwritten manuscript by Beethoven which was missing for 115 years has been put up for auction.
Grosse Fuge dates from the year before the composer died
The score of Grosse Fuge, which has the composer's changes, was found by a librarian at a US religious school.
It is expected to fetch up to £1.5m when it goes on sale at Sotheby's auction house in London on 1 December.
Sotheby's says the score, which was last seen at an auction in Berlin in 1890, is "the most important Beethoven manuscript to appear in recent memory".
The buyer at the 1890 Berlin auction is now believed to have been an industrialist from Ohio who took the manuscript to the US.
The German composer wrote Grosse Fuge while contending with deafness.
The score dates from 1826, the year before he died.
Dr Stephen Roe, head of Sotheby's manuscript department, said the discovery was "an amazing find".
"It has never before been seen or described by Beethoven scholars," he said.
"Its rediscovery will allow a complete reassessment of this extraordinary music."
It is not known how the manuscript was passed to the seminary
The score, which contains multiple deletions and corrections, was found by librarian Heather Carbo at the Palmer Theological Seminary in Philadelphia.
Ms Carbo was conducting an inventory of the seminary's archives when she came across the manuscript in a basement cabinet.
Manuscripts by Mozart were discovered at the seminary in 1990.
President Dr Wallace Charles Smith said: "At the time, we called it 'the Mozart miracle'. It seems appropriate that this time we are thankful for the 'Beethoven blessing'."
The last missing Beethoven manuscript to be discovered was found in Cornwall in 1999 and sold by Sotheby's for £166,500.