A rare book of Shakespeare's plays, considered to be one of the most important in British literature, is to be auctioned at Sotheby's in London.
The rare first folio is likely to raise £3m when auctioned in July
The complete first folio of the playwright's work had a print run of approximately 750 in 1623.
However, only a third of these survive and most of them are incomplete.
The book is being sold by Dr Williams's Theological Library in London, which hopes the proceeds - expected to be more than £3m - will secure its future.
No collected edition of Shakespeare's plays was published during his lifetime.
In 1623, seven years after his death, some of his friends put together a folio comprising 36 plays.
It was the first time that 18 of them - including Twelfth Night and Macbeth - had been printed.
Many of the plays have extensive annotations by readers
It is likely that they survive only because they were included in the book and would otherwise have been lost.
This edition is bound in brown leather and is full of annotations, marking interesting parts of the text.
Its 17th Century readers did not make notes beside passages now considered to be Shakespeare's most famous - Hamlet's "To be or not to be" speech, for instance.
Instead, they highlighted other sections such as those from Midsummer Night's Dream and Coriolanus.
One reader even corrected an error in the text in the second part of Henry VI, changing by hand three times the name Elinor to Margaret.
'Safeguard' library's future
The director of Dr Williams's Theological Library, Dr David Wykes, said: "The library has been proud to own this remarkable copy of Shakespeare's first folio.
"Its sale will secure the finances of the library and safeguard our important historical collections of manuscripts and printed books for future generations."
The book will be displayed at Sotheby's offices in London, Chicago, Los Angeles, New York, Beijing and Hong Kong in April and May, ahead of the auction on 13 July.