A professor of music has spent 10 years examining every note of every authentic source of every Beethoven piano sonata to produce what he feels is the truest representation of the composer's work.
Barry Cooper from The University of Manchester has published a revised version of all 35 sonatas - including three little-known pieces printed when the composer was 12 - for the Associated Board of the Royal Schools of Music.
Based at the University's School of Arts, Histories and Cultures, Professor Cooper, who is one of the world's leading Beethoven experts, has published the work in three volumes.
He is widely known for completing the first movement of Beethoven's unfinished tenth symphony, premiered at the Royal Festival Hall in 1988.
The thousands of notes examined for his latest work are accompanied by over 150,000 words of detailed commentary.
He said: "What I've done is try to reproduce what Beethoven actually wrote - and what he meant to write - more accurately than in any previous edition.
"For example, one note in particular has been the subject of debate ever since it was first published in the early 19th century - an A sharp in the opus 106 Sonata in B flat major known as the "Hammerklavier".
"Beethoven probably forgot to cancel the sharp and an 'A natural' makes more sense.
"And what I've also done, which has not been done before, is to relate what Beethoven wrote to what we know about the notation and performing styles of his day, wherever there's any uncertainty.
"This detailed commentary should be of great help for all performers.
"If you know the sonatas well, you'll certainly be able to tell the difference."
He added: "All other recent editions have 32 sonatas. The three extra ones are normally omitted as they were very early works written when Beethoven was 12.
"I feel there is no reason to omit them as they are full scale works.
"Moreover, the first complete edition of Beethoven's piano sonatas, published by Beethoven's friend Haslinger, did contain the extra three.
"As Beethoven himself may have been involved, it suggests he would have approved."
Leslie East, Executive Director: Syllabus & Publishing for ABRSM, commented: "The new edition of Beethoven's Piano Sonatas is a landmark in the history of music scholarship and publishing.
"Professor Cooper's remarkable forensic examination of the history and sources of this essential canon of the piano literature is matched by the immensely practical and educationally valuable insights he brings to issues of interpretation and performance.
"ABRSM Publishing is proud to be the publisher of an edition that provides a definitive text alongside such a uniquely comprehensive picture of these extraordinary works."
Source: University of Manchester
Explore further: Supermoon plus eclipse equals rare sky show Sunday night