The daughter of a Dambusters hero is offering a £5,000 reward for the return of her father's stolen logbook.
Shere Lowe has launched an appeal for information leading to the safe return of the book, which belonged to the late RAF Sergeant John Fraser, who took part in the famous mission to destroy dams in Nazi Germany on May 16 and 17 1943.
The logbook has been missing since it was lent to military historian Alexander Bateman, 48, in 1996 by Sgt Fraser's widow, Doris.
Bateman was jailed for two years at Wood Green Court in north London in February this year for stealing the treasured record.
He borrowed the memento for research but lied repeatedly when asked to return it and the item has never been recovered.
It is feared that it may have been sold.
Ms Lowe, who lives in Blaine, Washington in the US, said: "This is not a document, it's not a piece of paper, it's a piece of my father's legacy of courage.
"Because I lost him at such a young age, I value anything about my father and this is a record of what he did with 50 Squadron as well as 617 Squadron - the whole time he was active in the military."
Speaking while in the UK to mark the 74th anniversary of the Dambusters raid, Ms Lowe said: "Please help us to bring a piece of Dad home, instead of looking at it like it's a commodity."
Sgt Fraser was on of one of 133 Allied aircrew to take part in the Dambusters mission.
He moved to Canada with his wife after World War Two, but tragically died in an air accident in 1962, leaving behind three children.
Although the logbook was never found, during a search of Bateman's home police recovered the collection of 290 wartime images and asked Ms Lowe to ensure their safe return.
She presented the album to members of the family of Ken Earnshaw, a crewmate of her father's, during an emotional reunion at the Bomber Command Museum of Canada in Alberta last month.
Anyone with information about the logbook should contact the Metropolitan Police on 101 or Crimestoppers anonymously on 0800 555 111.